diff --git a/plugins/kolab_files/kolab_files.js b/plugins/kolab_files/kolab_files.js
index 3044d6e8..1759ee47 100644
--- a/plugins/kolab_files/kolab_files.js
+++ b/plugins/kolab_files/kolab_files.js
@@ -1,2344 +1,2644 @@
 /**
  * Kolab files plugin
  *
  * @author Aleksander Machniak <machniak@kolabsys.com>
  *
  * @licstart  The following is the entire license notice for the
  * JavaScript code in this file.
  *
  * Copyright (C) 2011, Kolab Systems AG <contact@kolabsys.com>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
  * published by the Free Software Foundation, either version 3 of the
  * License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  *
  * @licend  The above is the entire license notice
  * for the JavaScript code in this file.
  */
 
 window.rcmail && window.files_api && rcmail.addEventListener('init', function() {
   if (rcmail.task == 'mail') {
     // mail compose
     if (rcmail.env.action == 'compose') {
       var elem = $('#compose-attachments > div'),
         input = $('<input class="button" type="button">')
           .attr('tabindex', $('input', elem).attr('tabindex') || 0)
           .val(rcmail.gettext('kolab_files.fromcloud'))
           .click(function() { kolab_files_selector_dialog(); })
           .appendTo(elem);
 
       if (rcmail.gui_objects.filelist) {
         rcmail.file_list = new rcube_list_widget(rcmail.gui_objects.filelist, {
           multiselect: true,
           keyboard: true,
           column_movable: false,
           dblclick_time: rcmail.dblclick_time
         });
         rcmail.file_list.addEventListener('select', function(o) { kolab_files_list_select(o); })
           .addEventListener('listupdate', function(e) { rcmail.triggerEvent('listupdate', e); });
 
         rcmail.enable_command('files-sort', 'files-search', 'files-search-reset', true);
 
         rcmail.file_list.init();
         kolab_files_list_coltypes();
       }
 
       // register some commands to skip warning message on compose page
       $.merge(rcmail.env.compose_commands, ['files-list', 'files-sort', 'files-search', 'files-search-reset']);
     }
     // mail preview
     else if (rcmail.env.action == 'show' || rcmail.env.action == 'preview') {
       var attachment_list = $('#attachment-list');
 
       if ($('li', attachment_list).length) {
         var link = $('<a href="#" class="button filesaveall">')
           .text(rcmail.gettext('kolab_files.saveall'))
           .click(function() { kolab_directory_selector_dialog(); })
           .insertAfter(attachment_list);
       }
 
       rcmail.addEventListener('menu-open', kolab_files_attach_menu_open);
       rcmail.enable_command('folder-create', true);
     }
     // attachment preview
     else if (rcmail.env.action == 'get') {
       rcmail.enable_command('folder-create', true);
     }
 
     kolab_files_init();
   }
   else if (rcmail.task == 'files') {
     if (rcmail.gui_objects.filelist) {
       rcmail.file_list = new rcube_list_widget(rcmail.gui_objects.filelist, {
         multiselect: true,
         draggable: true,
         keyboard: true,
         column_movable: rcmail.env.col_movable,
         dblclick_time: rcmail.dblclick_time
       });
 
       rcmail.file_list.addEventListener('dblclick', function(o) { kolab_files_list_dblclick(o); })
         .addEventListener('select', function(o) { kolab_files_list_select(o); })
         .addEventListener('keypress', function(o) { kolab_files_list_keypress(o); })
         .addEventListener('dragstart', function(e) { kolab_files_drag_start(e); })
         .addEventListener('dragmove', function(e) { kolab_files_drag_move(e); })
         .addEventListener('dragend', function(e) { kolab_files_drag_end(e); })
         .addEventListener('column_replace', function(e) { kolab_files_set_coltypes(e); })
         .addEventListener('listupdate', function(e) { rcmail.triggerEvent('listupdate', e); });
 
       rcmail.enable_command('menu-open', 'menu-save', 'files-sort', 'files-search', 'files-search-reset', 'folder-create', true);
 
       rcmail.file_list.init();
       kolab_files_list_coltypes();
       kolab_files_drag_drop_init($(rcmail.gui_objects.filelist).parents('.droptarget'));
     }
 
     // "one file only" commands
     rcmail.env.file_commands = ['files-get'];
     // "one or more file" commands
     rcmail.env.file_commands_all = ['files-delete', 'files-move', 'files-copy'];
 
     kolab_files_init();
 
     if (rcmail.env.action == 'open') {
       rcmail.enable_command('files-get', 'files-delete', rcmail.env.file);
     }
     else {
       file_api.folder_list();
       file_api.browser_capabilities_check();
       rcmail.enable_command('folder-mount', rcmail.env.external_sources);
     }
   }
 });
 
 
 /**********************************************************/
 /*********          Shared functionality         **********/
 /**********************************************************/
 
 // Initializes API object
 function kolab_files_init()
 {
   if (window.file_api)
     return;
 
   // Initialize application object (don't change var name!)
   file_api = $.extend(new files_api(), new kolab_files_ui());
 
   file_api.set_env({
     token: kolab_files_token(),
     url: rcmail.env.files_url,
     sort_col: 'name',
     sort_reverse: false,
     search_threads: rcmail.env.search_threads,
     resources_dir: rcmail.assets_path('program/resources'),
+    caps: rcmail.env.files_caps,
     supported_mimetypes: rcmail.env.file_mimetypes
   });
 
   file_api.translations = rcmail.labels;
 };
 
 // returns API authorization token
 function kolab_files_token()
 {
   // consider the token from parent window more reliable (fresher) than in framed window
   // it's because keep-alive is not requested in frames
   return window.parent && parent.rcmail && parent.rcmail.env.files_token ? parent.rcmail.env.files_token : rcmail.env.files_token;
 };
 
 // folder selection dialog
 function kolab_directory_selector_dialog(id)
 {
   var dialog = $('#files-dialog'),
     input = $('#file-save-as-input'),
     form = $('#file-save-as'),
     list = $('#folderlistbox'),
     buttons = {}, label = 'saveto',
     win = window, fn;
 
   // attachment is specified
   if (id) {
     var attach = $('#attach' + id + '> a').first(),
       filename = attach.attr('title');
 
     if (!filename) {
       attach = attach.clone();
       $('.attachment-size', attach).remove();
       filename = $.trim(attach.text());
     }
 
     form.show();
     dialog.addClass('saveas');
     input.val(filename);
   }
   // attachment preview page
   else if (rcmail.env.action == 'get') {
     id = rcmail.env.part;
     form.show();
     dialog.addClass('saveas');
     input.val(rcmail.env.filename);
   }
   else {
     form.hide();
     dialog.removeClass('saveas');
     label = 'saveall';
   }
 
   $('#foldercreatelink').attr('tabindex', 0);
 
   buttons[rcmail.gettext('kolab_files.save')] = function () {
     if (!file_api.env.folder)
       return;
 
     var lock = rcmail.set_busy(true, 'saving'),
       request = {
         act: 'save-file',
         source: rcmail.env.mailbox,
         uid: rcmail.env.uid,
         dest: file_api.env.folder
       };
 
     if (id) {
       request.id = id;
       request.name = input.val();
     }
 
     rcmail.http_post('plugin.kolab_files', request, lock);
     kolab_dialog_close(this);
   };
 
   buttons[rcmail.gettext('kolab_files.cancel')] = function () {
     kolab_dialog_close(this);
   };
 
   if (!rcmail.env.folders_loaded) {
     fn = function() {
       file_api.folder_list();
       rcmail.env.folders_loaded = true;
     };
   }
 
   // show dialog window
   kolab_dialog_show(dialog, {
     title: rcmail.gettext('kolab_files.' + label),
     buttons: buttons,
     button_classes: ['mainaction'],
     minWidth: 250,
     minHeight: 300,
     height: 400,
     width: 300
   }, fn);
 
   // "enable" folder creation when dialog is displayed in parent window
   if (rcmail.is_framed() && !parent.rcmail.folder_create) {
     parent.rcmail.enable_command('folder-create', true);
     parent.rcmail.folder_create = function() {
       win.kolab_files_folder_create_dialog();
     };
   }
 };
 
 // file selection dialog
 function kolab_files_selector_dialog()
 {
   var dialog = $('#files-compose-dialog'), buttons = {};
 
   buttons[rcmail.gettext('kolab_files.attachsel')] = function () {
     var list = [];
     $('#filelist tr.selected').each(function() {
       list.push($(this).data('file'));
     });
 
     kolab_dialog_close(this);
 
     if (list.length) {
       // display upload indicator and cancel button
       var content = '<span>' + rcmail.get_label('kolab_files.attaching') + '</span>',
         id = new Date().getTime();
 
       rcmail.add2attachment_list(id, {name:'', html:content, classname:'uploading', complete:false});
 
       // send request
       rcmail.http_post('plugin.kolab_files', {
         act: 'attach-file',
         files: list,
         id: rcmail.env.compose_id,
         uploadid: id
       });
     }
   };
 
   buttons[rcmail.gettext('kolab_files.cancel')] = function () {
     kolab_dialog_close(this);
   };
 
   // show dialog window
   kolab_dialog_show(dialog, {
     title: rcmail.gettext('kolab_files.selectfiles'),
     buttons: buttons,
     button_classes: ['mainaction'],
     minWidth: 500,
     minHeight: 300,
     width: 700,
     height: 500
   }, function() { rcmail.file_list.resize(); });
 
   if (!rcmail.env.files_loaded) {
     file_api.folder_list();
     rcmail.env.files_loaded = true;
   }
   else {
     rcmail.file_list.clear_selection();
   }
 };
 
 function kolab_files_attach_menu_open(p)
 {
   if (!p || !p.props || p.props.menu != 'attachmentmenu')
     return;
 
   var id = p.props.id;
 
   $('#attachmenusaveas').unbind('click').attr('onclick', '').click(function(e) {
     return kolab_directory_selector_dialog(id);
   });
 };
 
 // folder creation dialog
 function kolab_files_folder_create_dialog()
 {
   var dialog = $('#files-folder-create-dialog'),
     buttons = {},
     select = $('select[name="parent"]', dialog).html(''),
     input = $('input[name="name"]', dialog).val('');
 
   buttons[rcmail.gettext('kolab_files.create')] = function () {
     var folder = '', name = input.val(), parent = select.val();
 
     if (!name)
       return;
 
     if (parent)
       folder = parent + file_api.env.directory_separator;
 
     folder += name;
 
     file_api.folder_create(folder);
     kolab_dialog_close(this);
   };
 
   buttons[rcmail.gettext('kolab_files.cancel')] = function () {
     kolab_dialog_close(this);
   };
 
   // show dialog window
   kolab_dialog_show(dialog, {
     title: rcmail.gettext('kolab_files.foldercreate'),
     buttons: buttons,
     button_classes: ['mainaction']
   });
 
   // Fix submitting form with Enter
   $('form', dialog).submit(kolab_dialog_submit_handler);
 
   // build parent selector
   select.append($('<option>').val('').text('---'));
   $.each(file_api.env.folders, function(i, f) {
     var n, option = $('<option>'), name = escapeHTML(f.name);
 
     for (n=0; n<f.depth; n++)
       name = '&nbsp;&nbsp;&nbsp;' + name;
 
     option.val(i).html(name).appendTo(select);
 
     if (i == file_api.env.folder)
       option.attr('selected', true);
   });
 };
 
 // folder edit dialog
 function kolab_files_folder_edit_dialog()
 {
   var dialog = $('#files-folder-edit-dialog'),
     buttons = {}, options = [],
     separator = file_api.env.directory_separator,
     arr = file_api.env.folder.split(separator),
     folder = arr.pop(),
     path = arr.join(separator),
     select = $('select[name="parent"]', dialog).html(''),
     input = $('input[name="name"]', dialog).val(folder);
 
   buttons[rcmail.gettext('kolab_files.save')] = function () {
     var folder = '', name = input.val(), parent = select.val();
 
     if (!name)
       return;
 
     if (parent)
       folder = parent + separator;
 
     folder += name;
 
     file_api.folder_rename(file_api.env.folder, folder);
     kolab_dialog_close(this);
   };
 
   buttons[rcmail.gettext('kolab_files.cancel')] = function () {
     kolab_dialog_close(this);
   };
 
   // show dialog window
   kolab_dialog_show(dialog, {
     title: rcmail.gettext('kolab_files.folderedit'),
     buttons: buttons,
     button_classes: ['mainaction']
   });
 
   // Fix submitting form with Enter
   $('form', dialog).submit(kolab_dialog_submit_handler);
 
   // build parent selector
   options.push($('<option>').val('').text('---'));
   $.each(file_api.env.folders, function(i, f) {
     var n, name = escapeHTML(f.name);
 
     for (n=0; n<f.depth; n++)
       name = '&nbsp;&nbsp;&nbsp;' + name;
 
     options.push($('<option>').val(i).html(name));
   });
 
   select.append(options).val(path);
 };
 
 // folder mounting dialog
 function kolab_files_folder_mount_dialog()
 {
   var args = {buttons: {}, title: rcmail.gettext('kolab_files.foldermount')},
     dialog = $('#files-folder-mount-dialog'),
     input = $('#folder-mount-name').val('');
 
   args.buttons[rcmail.gettext('kolab_files.save')] = function () {
     var args = {}, folder = input.val(),
       driver = $('input[name="driver"]:checked', dialog).val();
 
     if (!folder || !driver)
       return;
 
     args.folder = folder;
     args.driver = driver;
 
     $('#source-' + driver + ' input').each(function() {
       if (this.name.startsWith(driver + '[')) {
         args[this.name.substring(driver.length + 1, this.name.length - 1)] = this.value;
       }
     });
 
     $('.auth-options input', dialog).each(function() {
       args[this.name] = this.type == 'checkbox' && !this.checked ? '' : this.value;
     });
 
     file_api.folder_mount(args);
     kolab_dialog_close(this);
   };
 
   args.buttons[rcmail.gettext('kolab_files.cancel')] = function () {
     kolab_dialog_close(this);
   };
 
   // close folderoption menu
   rcmail.hide_menu('folderoptions');
 
   // initialize drivers list
   if (!rcmail.drivers_list_initialized) {
     rcmail.drivers_list_initialized = true;
 
     $('td.source', dialog).each(function() {
       $(this).click(function() {
         $('td.selected', dialog).removeClass('selected');
         dialog.find('.driverform').hide();
         $(this).addClass('selected').find('.driverform').show();
         $('input[type="radio"]', this).prop('checked', true);
      });
    });
   }
 
   args.button_classes = ['mainaction'];
 
   // show dialog window
   kolab_dialog_show(dialog, args, function() {
     $('td.source:first', dialog).click();
     input.focus();
   });
 };
 
 // file edition dialog
 function kolab_files_file_edit_dialog(file)
 {
   var dialog = $('#files-file-edit-dialog'),
     buttons = {}, name = file_api.file_name(file)
     input = $('input[name="name"]', dialog).val(name);
 
   buttons[rcmail.gettext('kolab_files.save')] = function () {
     var folder = file_api.file_path(file), name = input.val();
 
     if (!name)
       return;
 
     name = folder + file_api.env.directory_separator + name;
 
     // @TODO: now we only update filename
     if (name != file)
       file_api.file_rename(file, name);
     kolab_dialog_close(this);
   };
   buttons[rcmail.gettext('kolab_files.cancel')] = function () {
     kolab_dialog_close(this);
   };
 
   // Fix submitting form with Enter
   $('form', dialog).submit(kolab_dialog_submit_handler);
 
   // show dialog window
   kolab_dialog_show(dialog, {
     title: rcmail.gettext('kolab_files.fileedit'),
     buttons: buttons,
     button_classes: ['mainaction']
   });
 };
 
 function kolab_dialog_show(content, params, onopen)
 {
   params = $.extend({
     modal: true,
     resizable: true,
     closeOnEscape: (!bw.ie6 && !bw.ie7),  // disabled for performance reasons
     minWidth: 400,
     minHeight: 300,
     width: 500,
     height: 400
   }, params || {});
 
   // dialog close handler
   params.close = function(e, ui) {
     var elem, stack = rcmail.dialog_stack;
 
     content.appendTo(document.body).hide();
     $(this).parent().remove(); // remove dialog
 
     // focus previously focused element (guessed)
     stack.pop();
     if (stack.length) {
       elem = stack[stack.length-1].find('input[type!="hidden"]:not(:hidden):first');
       if (!elem.length)
         elem = stack[stack.length-1].parent().find('a[role="button"], .ui-dialog-buttonpane button').first();
     }
 
     (elem && elem.length ? elem : window).focus();
   };
 
   // display it as popup
   var dialog = rcmail.show_popup_dialog('', params.title, params.buttons, params);
 
   content.appendTo(dialog).show().find('input[type!="hidden"]:not(:hidden):first').focus();
 
   if (onopen) onopen(content);
 
   // save dialog reference, to handle focus when closing one of opened dialogs
   if (!rcmail.dialog_stack)
     rcmail.dialog_stack = [];
 
   rcmail.dialog_stack.push(dialog);
 };
 
 // Handle form submit with Enter key, click first dialog button instead
 function kolab_dialog_submit_handler()
 {
   $(this).parents('.ui-dialog').find('.ui-button').first().click();
   return false;
 };
 
 // Hides dialog
 function kolab_dialog_close(dialog)
 {
   (rcmail.is_framed() ? window.parent : window).$(dialog).dialog('close');
 };
 
 // smart upload button
 function kolab_files_upload_input(button)
 {
   var link = $(button),
     file = $('<input>'),
     offset = link.offset();
 
   function move_file_input(e) {
     file.css({top: (e.pageY - offset.top - 10) + 'px', left: (e.pageX - offset.left - 10) + 'px'});
   }
 
   file.attr({name: 'file[]', type: 'file', multiple: 'multiple', size: 5, title: link.attr('title'), tabindex: "-1"})
     .change(function() { rcmail.files_upload('#filesuploadform'); })
     .click(function() { setTimeout(function() { link.mouseleave(); }, 20); })
     // opacity:0 does the trick, display/visibility doesn't work
     .css({opacity: 0, cursor: 'pointer', outline: 'none', position: 'absolute'});
 
   // In FF and IE we need to move the browser file-input's button under the cursor
   // Thanks to the size attribute above we know the length of the input field
   if (bw.mz || bw.ie)
     file.css({marginLeft: '-80px'});
 
   // Note: now, I observe problem with cursor style on FF < 4 only
   // Need position: relative (Bug #2615)
   link.css({overflow: 'hidden', cursor: 'pointer', position: 'relative'})
     .mouseenter(function() { this.__active = true; })
     // place button under the cursor
     .mousemove(function(e) {
       if (rcmail.commands['files-upload'] && this.__active)
         move_file_input(e);
       // move the input away if button is disabled
       else
         $(this).mouseleave();
     })
     .mouseleave(function() {
       file.css({top: '-10000px', left: '-10000px'});
       this.__active = false;
     })
     .attr('onclick', '') // remove default button action
     .click(function(e) {
       // forward click if mouse-enter event was missed
       if (rcmail.commands['files-upload'] && !this.__active) {
         this.__active = true;
         move_file_input(e);
         file.trigger(e);
       }
     })
     .mouseleave() // initially disable/hide input
     .append(file);
 };
 
 
 /***********************************************************/
 /**********          Main functionality           **********/
 /***********************************************************/
 
 // for reordering column array (Konqueror workaround)
 // and for setting some message list global variables
 kolab_files_list_coltypes = function()
 {
   var n, list = rcmail.file_list;
 
   rcmail.env.subject_col = null;
 
   if ((n = $.inArray('name', rcmail.env.coltypes)) >= 0) {
     rcmail.env.subject_col = n;
     list.subject_col = n;
   }
 
   list.init_header();
 };
 
 kolab_files_set_list_options = function(cols, sort_col, sort_order)
 {
   var update = 0, i, idx, name, newcols = [], oldcols = rcmail.env.coltypes;
 
   if (sort_col === undefined)
     sort_col = rcmail.env.sort_col;
   if (!sort_order)
     sort_order = rcmail.env.sort_order;
 
   if (rcmail.env.sort_col != sort_col || rcmail.env.sort_order != sort_order) {
     update = 1;
     rcmail.set_list_sorting(sort_col, sort_order);
   }
 
   if (cols && cols.length) {
     // make sure new columns are added at the end of the list
     for (i=0; i<oldcols.length; i++) {
       name = oldcols[i];
       idx = $.inArray(name, cols);
       if (idx != -1) {
         newcols.push(name);
         delete cols[idx];
       }
     }
     for (i=0; i<cols.length; i++)
       if (cols[i])
         newcols.push(cols[i]);
 
     if (newcols.join() != oldcols.join()) {
       update += 2;
       oldcols = newcols;
     }
   }
 
   if (update == 1)
     rcmail.command('files-list', {sort: sort_col, reverse: sort_order == 'DESC'});
   else if (update) {
     rcmail.http_post('files/prefs', {
       kolab_files_list_cols: oldcols,
       kolab_files_sort_col: sort_col,
       kolab_files_sort_order: sort_order
       }, rcmail.set_busy(true, 'loading'));
   }
 };
 
 kolab_files_set_coltypes = function(list)
 {
   var i, found, name, cols = list.list.tHead.rows[0].cells;
 
   rcmail.env.coltypes = [];
 
   for (i=0; i<cols.length; i++)
     if (cols[i].id && cols[i].id.match(/^rcm/)) {
       name = cols[i].id.replace(/^rcm/, '');
       rcmail.env.coltypes.push(name);
     }
 
 //  if ((found = $.inArray('name', rcmail.env.coltypes)) >= 0)
 //    rcmail.env.subject_col = found;
   rcmail.env.subject_col = list.subject_col;
 
   rcmail.http_post('files/prefs', {kolab_files_list_cols: rcmail.env.coltypes});
 };
 
 kolab_files_list_dblclick = function(list)
 {
   rcmail.command('files-open');
 };
 
 kolab_files_list_select = function(list)
 {
   var selected = list.selection.length;
 
   rcmail.enable_command(rcmail.env.file_commands_all, selected);
   rcmail.enable_command(rcmail.env.file_commands, selected == 1);
 
     // reset all-pages-selection
 //  if (list.selection.length && list.selection.length != list.rowcount)
 //    rcmail.select_all_mode = false;
 
   // enable files-
   if (selected == 1) {
     // get file mimetype
     var type = $('tr.selected', list.list).data('type');
     rcmail.env.viewer = file_api.file_type_supported(type);
   }
   else
     rcmail.env.viewer = 0;
 /*
     ) {
 //      caps = this.browser_capabilities().join();
       href = '?' + $.param({_task: 'files', _action: 'open', file: file, viewer: viewer == 2 ? 1 : 0});
       var win = window.open(href, rcmail.html_identifier('rcubefile'+file));
       if (win)
         setTimeout(function() { win.focus(); }, 10);
     }
 */
   rcmail.enable_command('files-open', rcmail.env.viewer);
 };
 
 kolab_files_list_keypress = function(list)
 {
   if (list.modkey == CONTROL_KEY)
     return;
 
   if (list.key_pressed == list.ENTER_KEY)
     rcmail.command('files-open');
   else if (list.key_pressed == list.DELETE_KEY || list.key_pressed == list.BACKSPACE_KEY)
     rcmail.command('files-delete');
 };
 
 kolab_files_drag_start = function(e)
 {
   rcmail.env.drag_target = null;
 
   if (rcmail.folder_list)
     rcmail.folder_list.drag_start();
 };
 
 kolab_files_drag_end = function(e)
 {
   if (rcmail.folder_list) {
     rcmail.folder_list.drag_end();
 
     if (rcmail.env.drag_target) {
       var modkey = rcube_event.get_modifier(e),
         menu = rcmail.gui_objects.file_dragmenu;
 
       rcmail.file_list.draglayer.hide();
 
       if (menu && modkey == SHIFT_KEY && rcmail.commands['files-copy']) {
         var pos = rcube_event.get_mouse_pos(e);
         $(menu).css({top: (pos.y-10)+'px', left: (pos.x-10)+'px'}).show();
         return;
       }
 
       rcmail.command('files-move', rcmail.env.drag_target);
     }
   }
 };
 
 kolab_files_drag_move = function(e)
 {
   if (rcmail.folder_list) {
     var mouse = rcube_event.get_mouse_pos(e);
 
     rcmail.env.drag_target = rcmail.folder_list.intersects(mouse, true);
   }
 };
 
 kolab_files_drag_menu_action = function(command)
 {
   var menu = rcmail.gui_objects.file_dragmenu;
 
   if (menu)
     $(menu).hide();
 
   rcmail.command(command, rcmail.env.drag_target);
 };
 
 kolab_files_selected = function()
 {
   var files = [];
   $.each(rcmail.file_list.get_selection(), function(i, v) {
     var name, row = $('#rcmrow'+v);
 
     if (row.length == 1 && (name = row.data('file')))
       files.push(name);
   });
 
   return files;
 };
 
 kolab_files_frame_load = function(frame)
 {
   var win = frame.contentWindow;
 
   rcmail.file_editor = win.file_editor && win.file_editor.editable ? win.file_editor : null;
 
   if (rcmail.file_editor)
     rcmail.enable_command('files-edit', true);
 
   rcmail.enable_command('files-print', (rcmail.file_editor && rcmail.file_editor.printable) ||
     (rcmail.env.file_data && /^image\//i.test(rcmail.env.file_data.type)));
 
   // detect Print button and check if it can be accessed
   try {
     if ($('#fileframe').contents().find('#print').length)
       rcmail.enable_command('files-print', true);
   }
   catch(e) {};
 };
 
 // activate html5 file drop feature (if browser supports it)
 kolab_files_drag_drop_init = function(container)
 {
   if (!window.FormData && !(window.XMLHttpRequest && XMLHttpRequest.prototype && XMLHttpRequest.prototype.sendAsBinary)) {
     return;
   }
 
   if (!container.length)
     return;
 
   $(document.body).bind('dragover dragleave drop', function(e) {
     if (!file_api.env.folder)
       return;
 
     e.preventDefault();
     container[e.type == 'dragover' ? 'addClass' : 'removeClass']('active');
   });
 
   container.bind('dragover dragleave', function(e) {
     return kolab_files_drag_hover(e);
   })
   container.children('div').bind('dragover dragleave', function(e) {
     return kolab_files_drag_hover(e);
   })
   container.get(0).addEventListener('drop', function(e) {
       // abort event and reset UI
       kolab_files_drag_hover(e);
       return file_api.file_drop(e);
     }, false);
 };
 
 // handler for drag/drop on element
 kolab_files_drag_hover = function(e)
 {
   if (!file_api.env.folder)
     return;
 
   e.preventDefault();
   e.stopPropagation();
 
   var elem = $(e.target);
 
   if (!elem.hasClass('droptarget'))
     elem = elem.parents('.droptarget');
 
   elem[e.type == 'dragover' ? 'addClass' : 'removeClass']('hover');
 };
 
 // returns localized file size
 kolab_files_file_size = function(size)
 {
   var i, units = ['GB', 'MB', 'KB', 'B'];
 
   size = file_api.file_size(size);
 
   for (i = 0; i < units.length; i++)
     if (size.toUpperCase().indexOf(units[i]) > 0)
       return size.replace(units[i], rcmail.gettext(units[i]));
 
   return size;
 };
 
 kolab_files_progress_str = function(param)
 {
   var current, total = file_api.file_size(param.total).toUpperCase();
 
   if (total.indexOf('GB') > 0)
     current = parseFloat(param.current/1073741824).toFixed(1);
   else if (total.indexOf('MB') > 0)
     current = parseFloat(param.current/1048576).toFixed(1);
   else if (total.indexOf('KB') > 0)
     current = parseInt(param.current/1024);
   else
     current = param.current;
 
   total = kolab_files_file_size(param.total);
 
   return rcmail.gettext('uploadprogress')
     .replace(/\$percent/, param.percent + '%')
     .replace(/\$current/, current)
     .replace(/\$total/, total);
 };
 
 
 /***********************************************************/
 /**********              Commands                 **********/
 /***********************************************************/
 
 rcube_webmail.prototype.files_sort = function(props)
 {
   var params = {},
     sort_order = this.env.sort_order,
     sort_col = !this.env.disabled_sort_col ? props : this.env.sort_col;
 
   if (!this.env.disabled_sort_order)
     sort_order = this.env.sort_col == sort_col && sort_order == 'ASC' ? 'DESC' : 'ASC';
 
   // set table header and update env
   this.set_list_sorting(sort_col, sort_order);
 
   this.http_post('files/prefs', {kolab_files_sort_col: sort_col, kolab_files_sort_order: sort_order});
 
   params.sort = sort_col;
   params.reverse = sort_order == 'DESC';
 
   this.command('files-list', params);
 };
 
 rcube_webmail.prototype.files_search = function()
 {
   var value = $(this.gui_objects.filesearchbox).val();
 
   if (value)
     file_api.file_search(value, $('#search_all_folders').is(':checked'));
   else
     file_api.file_search_reset();
 };
 
 rcube_webmail.prototype.files_search_reset = function()
 {
   $(this.gui_objects.filesearchbox).val('');
 
   file_api.file_search_reset();
 };
 
 rcube_webmail.prototype.files_folder_delete = function()
 {
   if (confirm(this.get_label('kolab_files.folderdeleteconfirm')))
     file_api.folder_delete(file_api.env.folder);
 };
 
 rcube_webmail.prototype.files_delete = function()
 {
   if (!confirm(this.get_label('kolab_files.filedeleteconfirm')))
     return;
 
   var files = this.env.file ? [this.env.file] : kolab_files_selected();
   file_api.file_delete(files);
 };
 
 rcube_webmail.prototype.files_move = function(folder)
 {
   var files = kolab_files_selected();
   file_api.file_move(files, folder);
 };
 
 rcube_webmail.prototype.files_copy = function(folder)
 {
   var files = kolab_files_selected();
   file_api.file_copy(files, folder);
 };
 
 rcube_webmail.prototype.files_upload = function(form)
 {
   if (form)
     file_api.file_upload(form);
 };
 
 rcube_webmail.prototype.files_list = function(param)
 {
   // just rcmail wrapper, to handle command busy states
   file_api.file_list(param);
 }
 
 rcube_webmail.prototype.files_list_update = function(head)
 {
   var list = this.file_list;
 
   list.clear();
   $('thead', list.fixed_header ? list.fixed_header : list.list).html(head);
   kolab_files_list_coltypes();
   file_api.file_list();
 };
 
 rcube_webmail.prototype.files_get = function()
 {
   var files = this.env.file ? [this.env.file] : kolab_files_selected();
 
   if (files.length == 1)
     file_api.file_get(files[0], {'force-download': true});
 };
 
 rcube_webmail.prototype.files_open = function()
 {
   var files = kolab_files_selected();
 
   if (files.length == 1)
     file_api.file_open(files[0], rcmail.env.viewer);
 };
 
 // enable file editor
 rcube_webmail.prototype.files_edit = function()
 {
   if (this.file_editor) {
     this.file_editor.enable();
     this.enable_command('files-save', true);
   }
 };
 
 rcube_webmail.prototype.files_save = function()
 {
   if (!this.file_editor)
     return;
 
   // binary files like ODF need to be updated using FormData
   if (this.file_editor.getContentCallback) {
     if (!file_api.file_uploader_support())
       return;
 
     file_api.req = file_api.set_busy(true, 'saving');
 //    this.file_editor.disable();
     this.file_editor.getContentCallback(function(content, filename) {
       file_api.file_uploader([content], {
         action: 'file_update',
         params: {file: rcmail.env.file, info: 1, token: file_api.env.token},
         response_handler: 'file_save_response',
         fieldname: 'content',
         single: true
       });
     });
 
     return;
   }
 
   var content = this.file_editor.getContent();
 
   file_api.file_save(this.env.file, content);
 };
 
 rcube_webmail.prototype.files_print = function()
 {
   if (this.file_editor && this.file_editor.printable)
     this.file_editor.print();
   else if (/^image\//i.test(this.env.file_data.type)) {
     var frame = $('#fileframe').get(0),
       win = frame ? frame.contentWindow : null;
 
     if (win) {
       win.focus();
       win.print();
     }
   }
   else {
     // e.g. Print button in PDF viewer
     try {
       $('#fileframe').contents().find('#print').click();
     }
     catch(e) {};
   }
 };
 
 rcube_webmail.prototype.files_set_quota = function(p)
 {
   if (p.total && window.file_api) {
     p.used *= 1024;
     p.total *= 1024;
     p.title = file_api.file_size(p.used) + ' / ' + file_api.file_size(p.total)
         + ' (' + p.percent + '%)';
   }
 
   p.type = this.env.quota_type;
 
   this.set_quota(p);
 };
 
 rcube_webmail.prototype.folder_create = function()
 {
   kolab_files_folder_create_dialog();
 };
 
 rcube_webmail.prototype.folder_rename = function()
 {
   kolab_files_folder_edit_dialog();
 };
 
 rcube_webmail.prototype.folder_mount = function()
 {
   kolab_files_folder_mount_dialog();
 };
 
 
 /**********************************************************/
 /*********          Files API handler            **********/
 /**********************************************************/
 
 function kolab_files_ui()
 {
   this.requests = {};
   this.uploads = [];
 
 /*
   // Called on "session expired" session
   this.logout = function(response) {};
 
   // called when a request timed out
   this.request_timed_out = function() {};
 
   // called on start of the request
   this.set_request_time = function() {};
 
   // called on request response
   this.update_request_time = function() {};
 */
   // set state
   this.set_busy = function(a, message)
   {
     if (this.req)
       rcmail.hide_message(this.req);
 
     return rcmail.set_busy(a, message);
   };
 
   // displays error message
   this.display_message = function(label, type)
   {
     return rcmail.display_message(this.t(label), type);
   };
 
   this.http_error = function(request, status, err)
   {
     rcmail.http_error(request, status, err);
   };
 
   // folders list request
   this.folder_list = function()
   {
     this.req = this.set_busy(true, 'loading');
     this.request('folder_list', {}, 'folder_list_response');
   };
 
   // folder list response handler
   this.folder_list_response = function(response)
   {
     if (!this.response(response))
       return;
 
     var first, body, rows = [],
       elem = $('#files-folder-list'),
       searchbox = $('#foldersearch'),
       list = $('<ul class="treelist listing folderlist"></ul>'),
       collections = !rcmail.env.action.match(/^(preview|show)$/) ? ['audio', 'video', 'image', 'document'] : [];
 
     // try parent window if the list element does not exist
     // i.e. called from dialog in parent window
     if (!elem.length && window.parent && parent.rcmail) {
       body = window.parent.document.body;
       elem = $('#files-folder-list', body);
       searchbox = $('#foldersearch', body);
     }
 
-    elem.html('').append(list);
+    elem.html('');
 
     this.env.folders = this.folder_list_parse(response.result && response.result.list ? response.result.list : response.result);
 
     $.each(this.env.folders, function(i, f) {
       var row;
       if (row = file_api.folder_list_row(i, f)) {
         if (!first)
           first = i;
         rows.push(row);
       }
     });
 
     // add virtual collections
     $.each(collections, function(i, n) {
       var row = $('<li class="mailbox collection ' + n + '"></li>');
 
       row.attr('id', 'rcmli' + rcmail.html_identifier_encode('folder-collection-' + n))
         .append($('<a class="name"></a>').text(rcmail.gettext('kolab_files.collection_' + n)))
 
       rows.push(row);
     });
 
-    list.append(rows);
+    list.append(rows).appendTo(elem)
+      .on('click', 'a.subscription', function(e) {
+        return file_api.folder_list_subscription_button_click(this);
+      });
+
+    if (rcmail.folder_list) {
+      rcmail.folder_list.reset();
+      this.search_results_widget = null;
+    }
 
     // init treelist widget
     rcmail.folder_list = new rcube_treelist_widget(list, {
         selectable: true,
         id_prefix: 'rcmli',
         parent_focus: true,
         searchbox: searchbox,
         id_encode: rcmail.html_identifier_encode,
         id_decode: rcmail.html_identifier_decode,
         check_droptarget: function(node) {
           return !node.virtual
             && node.id != file_api.env.folder
             && $.inArray('collection', node.classes) == -1;
         }
     });
 
     rcmail.folder_list
       .addEventListener('collapse', function(node) { file_api.folder_collapsed(node); })
       .addEventListener('expand', function(node) { file_api.folder_collapsed(node); })
       .addEventListener('beforeselect', function(node) { return !rcmail.busy; })
-      .addEventListener('select', function(node) { file_api.folder_select(node.id); });
+      .addEventListener('search', function(search) { file_api.folder_search(search); })
+      .addEventListener('select', function(node) {
+        if (file_api.search_results_widget)
+          file_api.search_results_widget.select();
+        file_api.folder_select(node.id);
+      });
 
     // select first folder?
     if (response.result.auth_errors) { }
     else if (this.env.folder)
       rcmail.folder_list.select(this.env.folder);
     else if (this.env.collection)
       rcmail.folder_list.select('folder-collection-' + this.env.collection);
     else if (first)
       rcmail.folder_list.select(first);
 
     // add tree icons
 //    this.folder_list_tree(this.env.folders);
 
     // handle authentication errors on external sources
     this.folder_list_auth_errors(response.result);
   };
 
   this.folder_select = function(folder)
   {
     if (rcmail.busy)
       return;
 
     var is_collection = folder.match(/^folder-collection-(.*)$/),
       collection = RegExp.$1 || null;
 
     if (is_collection)
       folder = null;
 
     // search-reset can re-select the same folder, skip
     if (this.env.folder == folder && this.env.collection == collection)
       return;
 
     this.env.folder = folder;
     this.env.collection = collection;
 
     rcmail.enable_command('files-list', true);
     rcmail.enable_command('files-folder-delete', 'folder-rename', 'files-upload', !is_collection);
     rcmail.command('files-list', is_collection ? {collection: collection} : {folder: folder});
 
     this.quota();
   };
 
   this.folder_unselect = function()
   {
     rcmail.folder_list.select();
     this.env.folder = null;
     this.env.collection = null;
     rcmail.enable_command('files-folder-delete', 'files-upload', false);
   };
 
   this.folder_collapsed = function(node)
   {
     var prefname = 'kolab_files_collapsed_folders',
       old = rcmail.env[prefname],
       entry = '&' + urlencode(node.id) + '&';
 
     if (node.collapsed) {
       rcmail.env[prefname] = rcmail.env[prefname] + entry;
 
       // select the folder if one of its childs is currently selected
       // don't select if it's virtual (#1488346)
       if (!node.virtual && this.env.folder && this.env.folder.startsWith(node.id + '/')) {
         rcmail.folder_list.select(node.id);
       }
     }
     else {
       rcmail.env[prefname] = rcmail.env[prefname].replace(entry, '');
     }
 
     if (old !== rcmail.env[prefname] && (!rcmail.file_list || !rcmail.file_list.drag_active))
       rcmail.command('save-pref', {name: prefname, value: rcmail.env[prefname]});
   };
 
   this.folder_list_row = function(i, folder, parent)
   {
     var toggle, sublist, collapsed, parent, parent_name,
       row = $('<li class="mailbox"></li>'),
       id = 'rcmli' + rcmail.html_identifier_encode(i);
 
-    row.attr('id', id).append($('<a></a>').text(folder.name));
+    row.attr('id', id).append($('<a>').text(folder.name));
 
     if (folder.virtual)
       row.addClass('virtual');
+    else if (folder.subscribed !== undefined)
+      row.append(this.folder_list_subscription_button(folder.subscribed));
 
     folder.ref = row;
 
     if (folder.depth) {
       // find parent folder
       parent_name = i.replace(/\/[^/]+$/, '');
       if (!parent)
         parent = $(this.env.folders[parent_name].ref);
 
       toggle = $('div.treetoggle', parent);
       sublist = $('> ul', parent);
 
       if (!toggle.length) {
         collapsed = rcmail.env.kolab_files_collapsed_folders.indexOf('&' + urlencode(parent_name) + '&') > -1;
 
         toggle = $('<div>').attr('class', 'treetoggle' + (collapsed ? ' collapsed' : ' expanded'))
           .html('&nbsp;').appendTo(parent);
 
         sublist = $('<ul>').attr({role: 'group'}).appendTo(parent);
         if (collapsed)
           sublist.hide();
       }
 
       sublist.append(row);
     }
     else {
       return row;
     }
   };
 
+  // create subscription button element
+  this.folder_list_subscription_button = function(subscribed)
+  {
+    return $('<a>').attr({
+        title: rcmail.gettext('kolab_files.listpermanent'),
+        class: 'subscription' + (subscribed ? ' subscribed' : ''),
+        'aria-checked': subscribed,
+        role: 'checkbox'
+    });
+  };
+
+  // subscription button handler
+  this.folder_list_subscription_button_click = function(elem)
+  {
+    var folder = $(elem).parent('li').prop('id').replace(/^rcmli/, ''),
+      selected = $(elem).hasClass('subscribed');
+
+    folder = folder.replace(/--xsR$/, ''); // this might be a search result
+    folder = rcmail.html_identifier_decode(folder);
+    file_api['folder_' + (selected ? 'unsubscribe' : 'subscribe')](folder);
+    return false;
+  };
+
+  // sets subscription button status
+  this.folder_list_subscription_state = function(elem, status)
+  {
+    $(elem).children('a.subscription')
+      .prop('aria-checked', status)[status ? 'addClass' : 'removeClass']('subscribed');
+  };
+
+  // Folder searching handler (for unsubscribed folders)
+  this.folder_search = function(search)
+  {
+    // hide search results
+    if (this.search_results_widget) {
+      this.search_results_container.hide();
+      this.search_results_widget.reset();
+    }
+    this.search_results = {};
+
+    // send search request to the server
+    if (search.query && search.execute) {
+      // cancel previous search request
+      if (this.listsearch_request) {
+        this.listsearch_request.abort();
+        this.listsearch_request = null;
+      }
+
+      var params = {search: search.query, unsubscribed: 1};
+
+      this.req = this.set_busy(true, rcmail.gettext('searching'));
+      this.listsearch_request = this.request('folder_list', params, 'folder_search_response');
+    }
+    else if (!search.query) {
+      if (this.listsearch_request) {
+        this.listsearch_request.abort();
+        this.listsearch_request = null;
+      }
+
+      // any subscription changed, make sure the newly added records
+      // are listed before collections not after
+      if (this.folder_subscribe) {
+        var r, last, move = [], rows = $(rcmail.folder_list.container).children('li');
+
+        if (rows.length && !$(rows[rows.length-1]).hasClass('collection')) {
+          // collect all folders to move
+          while (rows.length--) {
+            r = $(rows[rows.length]);
+            if (r.hasClass('collection'))
+              last = r;
+            else if (last)
+              break;
+            else
+              move.push(r);
+          }
+
+          if (last)
+            $.each(move, function() {
+              this.remove();
+              last.before(this);
+            });
+        }
+      }
+    }
+  };
+
+  // folder search response handler
+  this.folder_search_response = function(response)
+  {
+    if (!this.response(response))
+      return;
+
+    var folders = response.result && response.result.list ? response.result.list : response.result;
+
+    if (!folders.length)
+      return;
+
+    folders = this.folder_list_parse(folders, 10000, false);
+
+    if (!this.search_results_widget) {
+      var list = rcmail.folder_list.container,
+        title = rcmail.gettext('kolab_files.additionalfolders'),
+        list_id = list.attr('id') || '0';
+
+      this.search_results_container = $('<div class="searchresults"></div>')
+          .append($('<h2 class="boxtitle" id="st:' + list_id + '"></h2>').text(title))
+          .insertAfter(list);
+
+      this.search_results_widget = new rcube_treelist_widget('<ul>', {
+          id_prefix: 'rcmli',
+          id_encode: rcmail.html_identifier_encode,
+          id_decode: rcmail.html_identifier_decode,
+          selectable: true
+      });
+
+      this.search_results_widget
+        .addEventListener('beforeselect', function(node) { return !rcmail.busy; })
+        .addEventListener('select', function(node) {
+          rcmail.folder_list.select();
+          file_api.folder_select(node.id);
+        });
+
+      this.search_results_widget.container
+        // copy classes from main list
+        .addClass(list.attr('class')).attr('aria-labelledby', 'st:' + list_id)
+        .appendTo(this.search_results_container)
+        .on('click', 'a.subscription', function(e) {
+          return file_api.folder_list_subscription_button_click(this);
+        });
+    }
+
+    // add results to the list
+    $.each(folders, function(i, folder) {
+      var node, separator = file_api.env.directory_separator,
+        path = i.split(separator),
+        html = [$('<a>').text(folder.name)];
+
+      // add subscription button
+      if (!folder.virtual)
+        html.push(file_api.folder_list_subscription_button(false));
+
+      path.pop();
+
+      file_api.search_results_widget.insert({
+          id: i,
+          classes: ['mailbox'],
+          text: folder.name,
+          html: html,
+          collapsed: false,
+          virtual: folder.virtual
+        }, path.length ? path.join(separator) : null);
+    });
+
+    this.search_results = folders;
+    this.search_results_container.show();
+  };
+
+  // folder subscribe request
+  this.folder_subscribe = function(folder)
+  {
+    this.env.folder_subscribe = folder;
+    this.req = this.set_busy(true, 'foldersubscribing');
+    this.request('folder_subscribe', {folder: folder}, 'folder_subscribe_response');
+  }
+
+  // folder subscribe response handler
+  this.folder_subscribe_response = function(response)
+  {
+    if (!this.response(response))
+      return;
+
+    this.display_message('foldersubscribed', 'confirmation');
+
+    var item, node = rcmail.folder_list.get_item(this.env.folder_subscribe);
+
+    if (this.search_results && this.search_results[this.env.folder_subscribe]) {
+      item = this.search_results_widget.get_item(this.env.folder_subscribe);
+      this.folder_list_subscription_state(item, true);
+      if (item = $(item).attr('id'))
+        this.folder_list_subscription_state($('#' + item.replace(/--xsR$/, '')), true);
+    }
+
+    // search result, move from search to main list widget
+    if (!node && this.search_results && this.search_results[this.env.folder_subscribe]) {
+      var i, html, dir, folder, separator = this.env.directory_separator,
+        path = this.env.folder_subscribe.split(separator);
+
+      // add all folders in a path to the main list if needed
+      // including the subscribed folder
+      for (i=0; i<path.length; i++) {
+        dir = path.slice(0, i + 1).join(separator);
+        node = rcmail.folder_list.get_node(dir);
+
+        if (!node) {
+          node = this.search_results_widget.get_node(dir);
+          if (!node) {
+            // sanity check
+            return;
+          }
+
+          if (i == path.length - 1) {
+            item = this.search_results_widget.get_item(dir);
+            this.folder_list_subscription_state(item, true);
+          }
+
+          folder = this.search_results[dir];
+          html = [$('<a>').text(folder.name)];
+          if (!folder.virtual)
+            html.push(this.folder_list_subscription_button(true));
+
+          node.html = html;
+          delete node.children;
+
+          rcmail.folder_list.insert(node, i > 0 ? path.slice(0, i).join(separator) : null);
+          // we're in search result, so there will be two records,
+          // add subscription button to the visible one, it was not cloned
+          if (!folder.virtual) {
+            node = rcmail.folder_list.get_item(dir);
+            $(node).append(file_api.folder_list_subscription_button(true));
+          }
+
+          this.env.folders[dir] = folder;
+        }
+      }
+
+      // now remove them from the search widget
+      while (path.length) {
+        dir = path.join(separator);
+        node = this.search_results_widget.get_item(dir);
+
+        if ($('ul[role="group"] > li', node).length)
+          break;
+
+        this.search_results_widget.remove(dir);
+
+        path.pop();
+      }
+
+      node = null;
+    }
+
+    if (node)
+      this.folder_list_subscription_state(node, true);
+
+    this.env.folders[this.env.folder_subscribe].subscribed = true;
+  };
+
+  // folder unsubscribe request
+  this.folder_unsubscribe = function(folder)
+  {
+    this.env.folder_subscribe = folder;
+    this.req = this.set_busy(true, 'folderunsubscribing');
+    this.request('folder_unsubscribe', {folder: folder}, 'folder_unsubscribe_response');
+  }
+
+  // folder unsubscribe response handler
+  this.folder_unsubscribe_response = function(response)
+  {
+    if (!this.response(response))
+      return;
+
+    this.display_message('folderunsubscribed', 'confirmation');
+
+    var folder = this.env.folders[this.env.folder_subscribe],
+      node = rcmail.folder_list.get_item(this.env.folder_subscribe);
+
+    if (this.search_results && this.search_results[this.env.folder_subscribe]) {
+      item = this.search_results_widget.get_item(this.env.folder_subscribe);
+
+      if (item) {
+        this.folder_list_subscription_state(item, false);
+        item = $('#' + $(item).attr('id').replace(/--xsR$/, ''));
+      }
+      else
+        item = $('#rcmli' + rcmail.html_identifier_encode(this.env.folder_subscribe), rcmail.folder_list.container);
+
+      this.folder_list_subscription_state(item, false);
+    }
+
+    this.folder_list_subscription_state(node, false);
+
+    folder.subscribed = false;
+  };
+
   // folder create request
   this.folder_create = function(folder)
   {
     this.req = this.set_busy(true, 'kolab_files.foldercreating');
     this.request('folder_create', {folder: folder}, 'folder_create_response');
   };
 
   // folder create response handler
   this.folder_create_response = function(response)
   {
     if (!this.response(response))
       return;
 
     this.display_message('kolab_files.foldercreatenotice', 'confirmation');
 
     // refresh folders list
     this.folder_list();
   };
 
   // folder rename request
   this.folder_rename = function(folder, new_name)
   {
     if (folder == new_name)
       return;
 
     this.env.folder_rename = new_name;
     this.req = this.set_busy(true, 'kolab_files.folderupdating');
     this.request('folder_move', {folder: folder, 'new': new_name}, 'folder_rename_response');
   };
 
   // folder create response handler
   this.folder_rename_response = function(response)
   {
     if (!this.response(response))
       return;
 
     this.display_message('kolab_files.folderupdatenotice', 'confirmation');
 
     // refresh folders and files list
     this.env.folder = this.env.folder_rename;
     this.folder_list();
   };
 
   // folder mount (external storage) request
   this.folder_mount = function(data)
   {
     this.req = this.set_busy(true, 'kolab_files.foldermounting');
     this.request('folder_create', data, 'folder_mount_response');
   };
 
   // folder create response handler
   this.folder_mount_response = function(response)
   {
     if (!this.response(response))
       return;
 
     this.display_message('kolab_files.foldermountnotice', 'confirmation');
 
     // refresh folders list
     this.folder_list();
   };
 
   // folder delete request
   this.folder_delete = function(folder)
   {
     this.req = this.set_busy(true, 'kolab_files.folderdeleting');
     this.request('folder_delete', {folder: folder}, 'folder_delete_response');
   };
 
   // folder delete response handler
   this.folder_delete_response = function(response)
   {
     if (!this.response(response))
       return;
 
     this.env.folder = null;
     rcmail.enable_command('files-folder-delete', 'folder-rename', 'files-list', false);
     this.display_message('kolab_files.folderdeletenotice', 'confirmation');
 
     // refresh folders list
     this.folder_list();
     this.quota();
   };
 
   // quota request
   this.quota = function()
   {
     if (rcmail.env.files_quota)
       this.request('quota', {folder: this.env.folder}, 'quota_response');
   };
 
   // quota response handler
   this.quota_response = function(response)
   {
     if (!this.response(response))
       return;
 
     rcmail.files_set_quota(response.result);
   };
 
   this.file_list = function(params)
   {
     if (!rcmail.gui_objects.filelist)
       return;
 
     if (!params)
       params = {};
 
     // reset all pending list requests
     for (i in this.requests) {
       this.requests[i].abort();
       rcmail.hide_message(i);
       delete this.requests[i];
     }
 
     if (params.all_folders) {
       params.collection = null;
       params.folder = null;
       this.folder_unselect();
     }
 
     if (params.collection == undefined)
       params.collection = this.env.collection;
     if (params.folder == undefined)
       params.folder = this.env.folder;
     if (params.sort == undefined)
       params.sort = this.env.sort_col;
     if (params.reverse == undefined)
       params.reverse = this.env.sort_reverse;
     if (params.search == undefined)
       params.search = this.env.search;
 
     this.env.folder = params.folder;
     this.env.collection = params.collection;
     this.env.sort_col = params.sort;
     this.env.sort_reverse = params.reverse;
 
     rcmail.enable_command(rcmail.env.file_commands, false);
     rcmail.enable_command(rcmail.env.file_commands_all, false);
 
     // empty the list
     this.env.file_list = [];
     rcmail.file_list.clear(true);
 
     // request
     if (params.collection || params.all_folders)
       this.file_list_loop(params);
     else if (this.env.folder) {
       params.req_id = this.set_busy(true, 'loading');
       this.requests[params.req_id] = this.request('file_list', params, 'file_list_response');
     }
   };
 
   // file list response handler
   this.file_list_response = function(response)
   {
     if (response.req_id)
       rcmail.hide_message(response.req_id);
 
     if (!this.response(response))
       return;
 
     var i = 0, list = [], table = $('#filelist');
 
     $.each(response.result, function(key, data) {
       var row = file_api.file_list_row(key, data, ++i);
       rcmail.file_list.insert_row(row);
       data.row = row;
       data.filename = key;
       list.push(data);
     });
 
     this.env.file_list = list;
     rcmail.file_list.resize();
   };
 
   // call file_list request for every folder (used for search and virt. collections)
   this.file_list_loop = function(params)
   {
     var i, folders = [], limit = Math.max(this.env.search_threads || 1, 1);
 
     if (params.collection) {
       if (!params.search)
         params.search = {};
       params.search['class'] = params.collection;
       delete params['collection'];
     }
 
     delete params['all_folders'];
 
     $.each(this.env.folders, function(i, f) {
       if (!f.virtual)
         folders.push(i);
     });
 
     this.env.folders_loop = folders;
     this.env.folders_loop_params = params;
     this.env.folders_loop_lock = false;
 
     for (i=0; i<folders.length && i<limit; i++) {
       params.req_id = this.set_busy(true, 'loading');
       params.folder = folders.shift();
       this.requests[params.req_id] = this.request('file_list', params, 'file_list_loop_response');
     }
   };
 
   // file list response handler for loop'ed request
   this.file_list_loop_response = function(response)
   {
     var i, folders = this.env.folders_loop,
       params = this.env.folders_loop_params,
       limit = Math.max(this.env.search_threads || 1, 1),
       valid = this.response(response);
 
     if (response.req_id)
       rcmail.hide_message(response.req_id);
 
     for (i=0; i<folders.length && i<limit; i++) {
       params.req_id = this.set_busy(true, 'loading');
       params.folder = folders.shift();
       this.requests[params.req_id] = this.request('file_list', params, 'file_list_loop_response');
     }
 
     rcmail.file_list.resize();
 
     if (!valid)
       return;
 
     this.file_list_loop_result_add(response.result);
   };
 
   // add files from list request to the table (with sorting)
   this.file_list_loop_result_add = function(result)
   {
     // chack if result (hash-array) is empty
     if (!object_is_empty(result))
       return;
 
     if (this.env.folders_loop_lock) {
       setTimeout(function() { file_api.file_list_loop_result_add(result); }, 100);
       return;
     }
 
     // lock table, other list responses will wait
     this.env.folders_loop_lock = true;
 
     var n, i, len, elem, list = [], rows = [],
       index = this.env.file_list.length,
       table = rcmail.file_list;
 
     for (n=0, len=index; n<len; n++) {
       elem = this.env.file_list[n];
       for (i in result) {
         if (this.sort_compare(elem, result[i]) < 0)
           break;
 
         var row = this.file_list_row(i, result[i], ++index);
         table.insert_row(row, elem.row);
         result[i].row = row;
         result[i].filename = i;
         list.push(result[i]);
         delete result[i];
       }
 
       list.push(elem);
     }
 
     // add the rest of rows
     $.each(result, function(key, data) {
       var row = file_api.file_list_row(key, data, ++index);
       table.insert_row(row);
       result[key].row = row;
       result[key].filename = key;
       list.push(result[key]);
     });
 
     this.env.file_list = list;
     this.env.folders_loop_lock = false;
   };
 
   // sort files list (without API request)
   this.file_list_sort = function(col, reverse)
   {
     var n, len, list = this.env.file_list,
       table = $('#filelist'), tbody = $('<tbody>');
 
     this.env.sort_col = col;
     this.env.sort_reverse = reverse;
 
     if (!list || !list.length)
       return;
 
     // sort the list
     list.sort(function (a, b) {
       return file_api.sort_compare(a, b);
     });
 
     // add rows to the new body
     for (n=0, len=list.length; n<len; n++) {
       tbody.append(list[n].row);
     }
 
     // replace table bodies
     $('tbody', table).replaceWith(tbody);
   };
 
   this.file_list_row = function(file, data, index)
   {
     var c, col, row = '';
 
     for (c in rcmail.env.coltypes) {
       c = rcmail.env.coltypes[c];
       if (c == 'name')
         col = '<td class="name filename ' + this.file_type_class(data.type) + '">'
           + '<span>' + escapeHTML(data.name) + '</span></td>';
       else if (c == 'mtime')
         col = '<td class="mtime">' + data.mtime + '</td>';
       else if (c == 'size')
         col = '<td class="size">' + this.file_size(data.size) + '</td>';
       else if (c == 'options')
         col = '<td class="options"><span></span></td>';
       else
         col = '<td class="' + c + '"></td>';
 
       row += col;
     }
 
     row = $('<tr>')
       .html(row)
       .attr({id: 'rcmrow' + index, 'data-file': file, 'data-type': data.type});
 
     $('td.options > span', row).click(function(e) {
       kolab_files_file_edit_dialog(file);
     });
 
     // collection (or search) lists files from all folders
     // display file name with full path as title
     if (!this.env.folder)
       $('td.name span', row).attr('title', file);
 
     return row.get(0);
   };
 
   this.file_search = function(value, all_folders)
   {
     if (value) {
       this.env.search = {name: value};
       rcmail.command('files-list', {search: this.env.search, all_folders: all_folders});
     }
     else
       this.search_reset();
   };
 
   this.file_search_reset = function()
   {
     if (this.env.search) {
       this.env.search = null;
       rcmail.command('files-list');
     }
   };
 
   this.file_get = function(file, params)
   {
     if (!params)
       params = {};
 
     params.token = this.env.token;
     params.file = file;
 
     rcmail.redirect(this.env.url + this.url('file_get', params));
   };
 
   // file(s) delete request
   this.file_delete = function(files)
   {
     this.req = this.set_busy(true, 'kolab_files.filedeleting');
     this.request('file_delete', {file: files}, 'file_delete_response');
   };
 
   // file(s) delete response handler
   this.file_delete_response = function(response)
   {
     if (!this.response(response))
       return;
 
     var rco, dir, self = this;
 
     this.display_message('kolab_files.filedeletenotice', 'confirmation');
 
     if (rcmail.env.file) {
       rco = rcmail.opener();
       dir = this.file_path(rcmail.env.file);
 
       // check if opener window contains files list, if not we can just close current window
       if (rco && rco.file_list && (opener.file_api.env.folder == dir || !opener.file_api.env.folder))
         self = opener.file_api;
       else
         window.close();
     }
 
     // @TODO: consider list modification "in-place" instead of full reload
     self.file_list();
     self.quota();
 
     if (rcmail.env.file)
       window.close();
   };
 
   // file(s) move request
   this.file_move = function(files, folder)
   {
     if (!files || !files.length || !folder)
       return;
 
     var count = 0, list = {};
 
     $.each(files, function(i, v) {
       var name = folder + file_api.env.directory_separator + file_api.file_name(v);
 
       if (name != v) {
         list[v] = name;
         count++;
       }
     });
 
     if (!count)
       return;
 
     this.req = this.set_busy(true, 'kolab_files.filemoving');
     this.request('file_move', {file: list}, 'file_move_response');
   };
 
   // file(s) move response handler
   this.file_move_response = function(response)
   {
     if (!this.response(response))
       return;
 
     if (response.result && response.result.already_exist && response.result.already_exist.length)
       this.file_move_ask_user(response.result.already_exist, true);
     else {
       this.display_message('kolab_files.filemovenotice', 'confirmation');
       this.file_list();
     }
   };
 
   // file(s) copy request
   this.file_copy = function(files, folder)
   {
     if (!files || !files.length || !folder)
       return;
 
     var count = 0, list = {};
 
     $.each(files, function(i, v) {
       var name = folder + file_api.env.directory_separator + file_api.file_name(v);
 
       if (name != v) {
         list[v] = name;
         count++;
       }
     });
 
     if (!count)
       return;
 
     this.req = this.set_busy(true, 'kolab_files.filecopying');
     this.request('file_copy', {file: list}, 'file_copy_response');
   };
 
   // file(s) copy response handler
   this.file_copy_response = function(response)
   {
     if (!this.response(response))
       return;
 
     if (response.result && response.result.already_exist && response.result.already_exist.length)
       this.file_move_ask_user(response.result.already_exist);
     else {
       this.display_message('kolab_files.filecopynotice', 'confirmation');
       this.quota();
     }
   };
 
   // when file move/copy operation returns file-exists error
   // this displays a dialog where user can decide to skip
   // or overwrite destination file(s)
   this.file_move_ask_user = function(list, move)
   {
     var file = list[0], buttons = {},
       text = rcmail.gettext('kolab_files.filemoveconfirm').replace('$file', file.dst)
       dialog = $('<div></div>');
 
     buttons[rcmail.gettext('kolab_files.fileoverwrite')] = function() {
       var file = list.shift(), f = {},
         action = move ? 'file_move' : 'file_copy';
 
       f[file.src] = file.dst;
       file_api.file_move_ask_list = list;
       file_api.file_move_ask_mode = move;
       dialog.dialog('destroy').remove();
       file_api.req = file_api.set_busy(true, move ? 'kolab_files.filemoving' : 'kolab_files.filecopying');
       file_api.request(action, {file: f, overwrite: 1}, 'file_move_ask_user_response');
     };
 
     if (list.length > 1)
       buttons[rcmail.gettext('kolab_files.fileoverwriteall')] = function() {
         var f = {}, action = move ? 'file_move' : 'file_copy';
 
         $.each(list, function() { f[this.src] = this.dst; });
         dialog.dialog('destroy').remove();
         file_api.req = file_api.set_busy(true, move ? 'kolab_files.filemoving' : 'kolab_files.filecopying');
         file_api.request(action, {file: f, overwrite: 1}, action + '_response');
       };
 
     var skip_func = function() {
       list.shift();
       dialog.dialog('destroy').remove();
 
       if (list.length)
         file_api.file_move_ask_user(list, move);
       else if (move)
         file_api.file_list();
     };
 
     buttons[rcmail.gettext('kolab_files.fileskip')] = skip_func;
 
     if (list.length > 1)
       buttons[rcmail.gettext('kolab_files.fileskipall')] = function() {
       dialog.dialog('destroy').remove();
         if (move)
           file_api.file_list();
       };
 
     // open jquery UI dialog
     kolab_dialog_show(dialog.html(text), {
       close: skip_func,
       buttons: buttons,
       minWidth: 400,
       width: 400
     });
   };
 
   // file move (with overwrite) response handler
   this.file_move_ask_user_response = function(response)
   {
     var move = this.file_move_ask_mode, list = this.file_move_ask_list;
 
     this.response(response);
 
     if (list && list.length)
       this.file_move_ask_user(list, mode);
     else {
       this.display_message('kolab_files.file' + (move ? 'move' : 'copy') + 'notice', 'confirmation');
       if (move)
         this.file_list();
     }
   };
 
   // file(s) rename request
   this.file_rename = function(oldfile, newfile)
   {
     this.req = this.set_busy(true, 'kolab_files.fileupdating');
     this.request('file_move', {file: oldfile, 'new': newfile}, 'file_rename_response');
   };
 
   // file(s) move response handler
   this.file_rename_response = function(response)
   {
     if (!this.response(response))
       return;
 
     // @TODO: we could update metadata instead
     this.file_list();
   };
 
   // file upload request
   this.file_upload = function(form)
   {
     var form = $(form),
       field = $('input[type=file]', form).get(0),
       files = field.files ? field.files.length : field.value ? 1 : 0;
 
     if (!files || !this.file_upload_size_check(field.files))
       return;
 
     // submit form and read server response
     this.file_upload_form(form, 'file_upload', function(event) {
       var doc, response;
       try {
         doc = this.contentDocument ? this.contentDocument : this.contentWindow.document;
         response = doc.body.innerHTML;
         // response may be wrapped in <pre> tag
         if (response.slice(0, 5).toLowerCase() == '<pre>' && response.slice(-6).toLowerCase() == '</pre>') {
           response = doc.body.firstChild.firstChild.nodeValue;
         }
         response = eval('(' + response + ')');
       }
       catch (err) {
         response = {status: 'ERROR'};
       }
 
       file_api.file_upload_progress_stop(event.data.ts);
 
       // refresh the list on upload success
       file_api.file_upload_response(response);
     });
   };
 
   // refresh the list on upload success
   this.file_upload_response = function(response)
   {
     if (this.response_parse(response)) {
        this.file_list();
        this.quota();
     }
   };
 
   // check upload max size
   this.file_upload_size_check = function(files)
   {
     var i, size = 0, maxsize = rcmail.env.files_max_upload;
 
     if (maxsize && files) {
       for (i=0; i < files.length; i++)
         size += files[i].size || files[i].fileSize;
 
       if (size > maxsize) {
         alert(rcmail.get_label('kolab_files.uploadsizeerror').replace('$size', kolab_files_file_size(maxsize)));
         return false;
       }
     }
 
     return true;
   };
 
   // post the given form to a hidden iframe
   this.file_upload_form = function(form, action, onload)
   {
     var ts = new Date().getTime(),
       frame_name = 'fileupload' + ts;
 
     // upload progress support
     if (rcmail.env.files_progress_name) {
       var fname = rcmail.env.files_progress_name,
         field = $('input[name='+fname+']', form);
 
       if (!field.length) {
         field = $('<input>').attr({type: 'hidden', name: fname});
         field.prependTo(form);
       }
 
       field.val(ts);
       this.file_upload_progress(ts, true);
     }
 
     rcmail.display_progress({name: ts});
 
     // have to do it this way for IE
     // otherwise the form will be posted to a new window
     if (document.all) {
       var html = '<iframe id="'+frame_name+'" name="'+frame_name+'"'
         + ' src="' + rcmail.assets_path('program/resources/blank.gif') + '"'
         + ' style="width:0;height:0;visibility:hidden;"></iframe>';
       document.body.insertAdjacentHTML('BeforeEnd', html);
     }
     // for standards-compliant browsers
     else
       $('<iframe>')
         .attr({name: frame_name, id: frame_name})
         .css({border: 'none', width: 0, height: 0, visibility: 'hidden'})
         .appendTo(document.body);
 
     // handle upload errors, parsing iframe content in onload
     $('#'+frame_name).on('load', {ts:ts}, onload);
 
     $(form).attr({
       target: frame_name,
       action: this.env.url + this.url(action, {folder: this.env.folder, token: this.env.token}),
       method: 'POST'
     }).attr(form.encoding ? 'encoding' : 'enctype', 'multipart/form-data')
       .submit();
   };
 
   // handler when files are dropped to a designated area.
   // compose a multipart form data and submit it to the server
   this.file_drop = function(e)
   {
     var files = e.target.files || e.dataTransfer.files;
 
     if (!files || !files.length || !this.file_upload_size_check(files))
       return;
 
     // prepare multipart form data composition
     var ts = new Date().getTime(),
       formdata = window.FormData ? new FormData() : null,
       fieldname = 'file[]',
       boundary = '------multipartformboundary' + (new Date).getTime(),
       dashdash = '--', crlf = '\r\n',
       multipart = dashdash + boundary + crlf;
 
     // inline function to submit the files to the server
     var submit_data = function() {
       var multiple = files.length > 1;
 
       rcmail.display_progress({name: ts});
       if (rcmail.env.files_progress_name)
         file_api.file_upload_progress(ts, true);
 
       // complete multipart content and post request
       multipart += dashdash + boundary + dashdash + crlf;
 
       $.ajax({
         type: 'POST',
         dataType: 'json',
         url: file_api.env.url + file_api.url('file_upload', {folder: file_api.env.folder}),
         contentType: formdata ? false : 'multipart/form-data; boundary=' + boundary,
         processData: false,
         timeout: 0, // disable default timeout set in ajaxSetup()
         data: formdata || multipart,
         headers: {'X-Session-Token': file_api.env.token},
         success: function(data) {
           file_api.file_upload_progress_stop(ts);
           file_api.file_upload_response(data);
         },
         error: function(o, status, err) {
           file_api.file_upload_progress_stop(ts);
           rcmail.http_error(o, status, err);
         },
         xhr: function() {
           var xhr = jQuery.ajaxSettings.xhr();
           if (!formdata && xhr.sendAsBinary)
             xhr.send = xhr.sendAsBinary;
           return xhr;
         }
       });
     };
 
     // upload progress supported (and handler exists)
     // add progress ID to the request - need to be added before files
     if (rcmail.env.files_progress_name) {
       if (formdata)
         formdata.append(rcmail.env.files_progress_name, ts);
       else
         multipart += 'Content-Disposition: form-data; name="' + rcmail.env.files_progress_name + '"'
           + crlf + crlf + ts + crlf + dashdash + boundary + crlf;
     }
 
     // get contents of all dropped files
     var f, j, i = 0, last = files.length - 1;
     for (j = 0; j <= last && (f = files[i]); i++) {
       if (!f.name) f.name = f.fileName;
       if (!f.size) f.size = f.fileSize;
       if (!f.type) f.type = 'application/octet-stream';
 
       // file name contains non-ASCII characters, do UTF8-binary string conversion.
       if (!formdata && /[^\x20-\x7E]/.test(f.name))
         f.name_bin = unescape(encodeURIComponent(f.name));
 
       // do it the easy way with FormData (FF 4+, Chrome 5+, Safari 5+)
       if (formdata) {
         formdata.append(fieldname, f);
         if (j == last)
           return submit_data();
       }
       // use FileReader supporetd by Firefox 3.6
       else if (window.FileReader) {
         var reader = new FileReader();
 
         // closure to pass file properties to async callback function
         reader.onload = (function(file, j) {
           return function(e) {
             multipart += 'Content-Disposition: form-data; name="' + fieldname + '"';
             multipart += '; filename="' + (f.name_bin || file.name) + '"' + crlf;
             multipart += 'Content-Length: ' + file.size + crlf;
             multipart += 'Content-Type: ' + file.type + crlf + crlf;
             multipart += reader.result + crlf;
             multipart += dashdash + boundary + crlf;
 
             if (j == last)  // we're done, submit the data
               return submit_data();
           }
         })(f,j);
         reader.readAsBinaryString(f);
       }
 
       j++;
     }
   };
 
   // upload progress requests
   this.file_upload_progress = function(id, init)
   {
     if (init && id)
       this.uploads[id] = this.env.folder;
 
     setTimeout(function() {
       if (id && file_api.uploads[id])
         file_api.request('upload_progress', {id: id}, 'file_upload_progress_response');
     }, rcmail.env.files_progress_time * 1000);
   };
 
   // upload progress response
   this.file_upload_progress_response = function(response)
   {
     if (!this.response(response))
       return;
 
     var param = response.result;
 
     if (!param.id || !this.uploads[param.id])
       return;
 
     if (param.total) {
       param.name = param.id;
 
       if (!param.done)
         param.text = kolab_files_progress_str(param);
 
       rcmail.display_progress(param);
     }
 
     if (!param.done && param.total)
       this.file_upload_progress(param.id);
     else
       delete this.uploads[param.id];
   };
 
   this.file_upload_progress_stop = function(id)
   {
     if (id) {
       delete this.uploads[id];
       rcmail.display_progress({name: id});
     }
   };
 
   // open file in new window, using file API viewer
   this.file_open = function(file, viewer)
   {
     var href = '?' + $.param({_task: 'files', _action: 'open', file: file, viewer: viewer == 2 ? 1 : 0});
     rcmail.open_window(href, false, true);
   };
 
   // save file
   this.file_save = function(file, content)
   {
     rcmail.enable_command('files-save', false);
     // because we currently can edit only text files
     // and we do not expect them to be very big, we save
     // file in a very simple way, no upload progress, etc.
     this.req = this.set_busy(true, 'saving');
     this.request('file_update', {file: file, content: content, info: 1}, 'file_save_response');
   };
 
   // file save response handler
   this.file_save_response = function(response)
   {
     rcmail.enable_command('files-save', true);
 
     if (!this.response(response))
       return;
 
     // update file properties table
     var table = $('#fileinfobox table'), file = response.result;
 
     if (file) {
       $('td.filetype', table).text(file.type);
       $('td.filesize', table).text(this.file_size(file.size));
       $('td.filemtime', table).text(file.mtime);
     }
   };
 
   // handle auth errors on folder list
   this.folder_list_auth_errors = function(result)
   {
     if (result && result.auth_errors) {
       if (!this.auth_errors)
         this.auth_errors = {};
 
       $.extend(this.auth_errors, result.auth_errors);
     }
 
     // ask for password to the first storage on the list
     $.each(this.auth_errors || [], function(i, v) {
       file_api.folder_list_auth_dialog(i, v);
       return false;
     });
   };
 
   // create dialog for user credentials of external storage
   this.folder_list_auth_dialog = function(label, driver)
   {
     var args = {width: 400, height: 300, buttons: {}},
       dialog = $('#files-folder-auth-dialog'),
       content = this.folder_list_auth_form(driver);
 
     dialog.find('table.propform').remove();
     $('.auth-options', dialog).before(content);
 
     args.buttons[this.t('kolab_files.save')] = function() {
       var data = {folder: label, list: 1};
 
       $('input', dialog).each(function() {
         data[this.name] = this.type == 'checkbox' && !this.checked ? '' : this.value;
       });
 
       file_api.open_dialog = this;
       file_api.req = file_api.set_busy(true, 'kolab_files.authenticating');
       file_api.request('folder_auth', data, 'folder_auth_response');
     };
 
     args.buttons[this.t('kolab_files.cancel')] = function() {
       delete file_api.auth_errors[label];
       kolab_dialog_close(this);
       // go to the next one
       file_api.folder_list_auth_errors();
     };
 
     args.title = this.t('kolab_files.folderauthtitle').replace('$title', label);
 
     // show dialog window
     kolab_dialog_show(dialog, args, function() {
       // focus first empty input
       $('input', dialog).each(function() {
         if (!this.value) {
           this.focus();
           return false;
         }
       });
     });
   };
 
   // folder_auth handler
   this.folder_auth_response = function(response)
   {
     if (!this.response(response))
       return;
 
     var folders, found,
       folder = response.result.folder,
       id = 'rcmli' + rcmail.html_identifier_encode(folder),
       parent = $('#' + id);
 
     // try parent window if the folder element does not exist
     if (!parent.length && window.parent && window.parent.rcmail) {
       parent = $('#' + id, window.parent.document.body);
     }
 
     delete this.auth_errors[folder];
     kolab_dialog_close(this.open_dialog);
 
     // go to the next one
     this.folder_list_auth_errors();
 
     // parse result
     folders = this.folder_list_parse(response.result.list);
     delete folders[folder]; // remove root added in folder_list_parse()
 
     // add folders from the external source to the list
     $.each(folders, function(i, f) {
       file_api.folder_list_row(i, f, parent.get(0));
       found = true;
     });
 
     // reset folders list widget
     if (found)
       rcmail.folder_list.reset(true);
 
     // add tree icons
 //    this.folder_list_tree(folders);
 
     $.extend(this.env.folders, folders);
   };
 
   // returns content of the external storage authentication form
   this.folder_list_auth_form = function(driver)
   {
     var rows = [];
 
     $.each(driver.form, function(fi, fv) {
       var id = 'authinput' + fi,
         attrs = {type: fi.match(/pass/) ? 'password' : 'text', size: 25, name: fi, id: id},
         input = $('<input>').attr(attrs);
 
       if (driver.form_values && driver.form_values[fi])
         input.attr({value: driver.form_values[fi]});
 
       rows.push($('<tr>')
         .append($('<td class="title">').append($('<label>').attr('for', id).text(fv)))
         .append($('<td>').append(input))
       );
     });
 
     return $('<table class="propform">').append(rows);
   };
 };
diff --git a/plugins/kolab_files/lib/kolab_files_engine.php b/plugins/kolab_files/lib/kolab_files_engine.php
index b367a217..15e3a999 100644
--- a/plugins/kolab_files/lib/kolab_files_engine.php
+++ b/plugins/kolab_files/lib/kolab_files_engine.php
@@ -1,1190 +1,1210 @@
 <?php
 
 /**
  * Kolab files storage engine
  *
  * @version @package_version@
  * @author Aleksander Machniak <machniak@kolabsys.com>
  *
  * Copyright (C) 2013, Kolab Systems AG <contact@kolabsys.com>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
  * published by the Free Software Foundation, either version 3 of the
  * License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
 class kolab_files_engine
 {
     private $plugin;
     private $rc;
     private $timeout = 600;
     private $sort_cols = array('name', 'mtime', 'size');
 
     const API_VERSION = 2;
 
 
     /**
      * Class constructor
      */
     public function __construct($plugin, $url)
     {
         $this->url     = rcube_utils::resolve_url($url);
         $this->plugin  = $plugin;
         $this->rc      = $plugin->rc;
         $this->timeout = $this->rc->config->get('session_lifetime') * 60;
     }
 
     /**
      * User interface initialization
      */
     public function ui()
     {
         $this->plugin->add_texts('localization/');
 
         // set templates of Files UI and widgets
         if ($this->rc->task == 'mail') {
             if ($this->rc->action == 'compose') {
                 $template = 'compose_plugin';
             }
             else if (in_array($this->rc->action, array('show', 'preview', 'get'))) {
                 $template = 'message_plugin';
 
                 if ($this->rc->action == 'get') {
                     // add "Save as" button into attachment toolbar
                     $this->plugin->add_button(array(
                         'id'         => 'saveas',
                         'name'       => 'saveas',
                         'type'       => 'link',
                         'onclick'    => 'kolab_directory_selector_dialog()',
                         'class'      => 'button buttonPas saveas',
                         'classact'   => 'button saveas',
                         'label'      => 'kolab_files.save',
                         'title'      => 'kolab_files.saveto',
                         ), 'toolbar');
                 }
                 else {
                     // add "Save as" button into attachment menu
                     $this->plugin->add_button(array(
                         'id'         => 'attachmenusaveas',
                         'name'       => 'attachmenusaveas',
                         'type'       => 'link',
                         'wrapper'    => 'li',
                         'onclick'    => 'return false',
                         'class'      => 'icon active saveas',
                         'classact'   => 'icon active saveas',
                         'innerclass' => 'icon active saveas',
                         'label'      => 'kolab_files.saveto',
                         ), 'attachmentmenu');
                 }
             }
 
+            $this->folder_list_env();
+
             $this->plugin->add_label('save', 'cancel', 'saveto',
                 'saveall', 'fromcloud', 'attachsel', 'selectfiles', 'attaching',
                 'collection_audio', 'collection_video', 'collection_image', 'collection_document',
                 'folderauthtitle', 'authenticating'
             );
         }
         else if ($this->rc->task == 'files') {
             $template = 'files';
 
             // get list of external sources
             $this->get_external_storage_drivers();
         }
 
         // add taskbar button
         if (empty($_REQUEST['framed'])) {
             $this->plugin->add_button(array(
                 'command'    => 'files',
                 'class'      => 'button-files',
                 'classsel'   => 'button-files button-selected',
                 'innerclass' => 'button-inner',
                 'label'      => 'kolab_files.files',
                 ), 'taskbar');
         }
 
         $this->plugin->include_stylesheet($this->plugin->local_skin_path().'/style.css');
 
         if (!empty($template)) {
             $collapsed_folders = (string) $this->rc->config->get('kolab_files_collapsed_folders');
 
             $this->plugin->include_script($this->url . '/js/files_api.js');
             $this->plugin->include_script('kolab_files.js');
             $this->rc->output->include_script('treelist.js');
             $this->rc->output->set_env('files_url', $this->url . '/api/');
             $this->rc->output->set_env('files_token', $this->get_api_token());
             $this->rc->output->set_env('kolab_files_collapsed_folders', $collapsed_folders);
 
             // register template objects for dialogs (and main interface)
             $this->rc->output->add_handlers(array(
                 'folder-create-form' => array($this, 'folder_create_form'),
                 'folder-edit-form'   => array($this, 'folder_edit_form'),
                 'folder-mount-form'  => array($this, 'folder_mount_form'),
                 'folder-auth-options'=> array($this, 'folder_auth_options'),
                 'file-search-form'   => array($this, 'file_search_form'),
                 'file-edit-form'     => array($this, 'file_edit_form'),
                 'filelist'           => array($this, 'file_list'),
                 'filequotadisplay'   => array($this, 'quota_display'),
             ));
 
             if ($this->rc->task != 'files') {
                 // add dialog content at the end of page body
                 $this->rc->output->add_footer(
                     $this->rc->output->parse('kolab_files.' . $template, false, false));
             }
         }
     }
 
     /**
      * Engine actions handler
      */
     public function actions()
     {
         if ($this->rc->task == 'files' && $this->rc->action) {
             $action = $this->rc->action;
         }
         else if ($this->rc->task != 'files' && $_POST['act']) {
             $action = $_POST['act'];
         }
         else {
             $action = 'index';
         }
 
         $method = 'action_' . str_replace('-', '_', $action);
 
         if (method_exists($this, $method)) {
             $this->plugin->add_texts('localization/');
             $this->{$method}();
         }
     }
 
     /**
      * Template object for folder creation form
      */
     public function folder_create_form($attrib)
     {
         $attrib['name'] = 'folder-create-form';
         if (empty($attrib['id'])) {
             $attrib['id'] = 'folder-create-form';
         }
 
         $input_name    = new html_inputfield(array('id' => 'folder-name', 'name' => 'name', 'size' => 30));
         $select_parent = new html_select(array('id' => 'folder-parent', 'name' => 'parent'));
         $table         = new html_table(array('cols' => 2, 'class' => 'propform'));
 
         $table->add('title', html::label('folder-name', rcube::Q($this->plugin->gettext('foldername'))));
         $table->add(null, $input_name->show());
         $table->add('title', html::label('folder-parent', rcube::Q($this->plugin->gettext('folderinside'))));
         $table->add(null, $select_parent->show());
 
         $out = $table->show();
 
         // add form tag around text field
         if (empty($attrib['form'])) {
             $out = $this->rc->output->form_tag($attrib, $out);
         }
 
         $this->plugin->add_label('foldercreating', 'foldercreatenotice', 'create', 'foldercreate', 'cancel');
         $this->rc->output->add_gui_object('folder-create-form', $attrib['id']);
 
         return $out;
     }
 
     /**
      * Template object for folder editing form
      */
     public function folder_edit_form($attrib)
     {
         $attrib['name'] = 'folder-edit-form';
         if (empty($attrib['id'])) {
             $attrib['id'] = 'folder-edit-form';
         }
 
         $input_name    = new html_inputfield(array('id' => 'folder-edit-name', 'name' => 'name', 'size' => 30));
         $select_parent = new html_select(array('id' => 'folder-edit-parent', 'name' => 'parent'));
         $table         = new html_table(array('cols' => 2, 'class' => 'propform'));
 
         $table->add('title', html::label('folder-name', rcube::Q($this->plugin->gettext('foldername'))));
         $table->add(null, $input_name->show());
         $table->add('title', html::label('folder-parent', rcube::Q($this->plugin->gettext('folderinside'))));
         $table->add(null, $select_parent->show());
 
         $out = $table->show();
 
         // add form tag around text field
         if (empty($attrib['form'])) {
             $out = $this->rc->output->form_tag($attrib, $out);
         }
 
         $this->plugin->add_label('folderupdating', 'folderupdatenotice', 'save', 'folderedit', 'cancel');
         $this->rc->output->add_gui_object('folder-edit-form', $attrib['id']);
 
         return $out;
     }
 
     /**
      * Template object for folder mounting form
      */
     public function folder_mount_form($attrib)
     {
         $sources = $this->rc->output->get_env('external_sources');
 
         if (empty($sources) || !is_array($sources)) {
             return '';
         }
 
         $attrib['name'] = 'folder-mount-form';
         if (empty($attrib['id'])) {
             $attrib['id'] = 'folder-mount-form';
         }
 
         // build form content
         $table        = new html_table(array('cols' => 2, 'class' => 'propform'));
         $input_name   = new html_inputfield(array('id' => 'folder-mount-name', 'name' => 'name', 'size' => 30));
         $input_driver = new html_radiobutton(array('name' => 'driver', 'size' => 30));
 
         $table->add('title', html::label('folder-mount-name', rcube::Q($this->plugin->gettext('name'))));
         $table->add(null, $input_name->show());
 
         foreach ($sources as $key => $source) {
             $id    = 'source-' . $key;
             $form  = new html_table(array('cols' => 2, 'class' => 'propform driverform'));
 
             foreach ((array) $source['form'] as $idx => $label) {
                 $iid = $id . '-' . $idx;
                 $type  = stripos($idx, 'pass') !== false ? 'html_passwordfield' : 'html_inputfield';
                 $input = new $type(array('size' => 30));
 
                 $form->add('title', html::label($iid, rcube::Q($label)));
                 $form->add(null, $input->show('', array(
                         'id'   => $iid,
                         'name' => $key . '[' . $idx . ']'
                 )));
             }
 
             $row = $input_driver->show(null, array('value' => $key))
                 . html::img(array('src' => $source['image'], 'alt' => $key, 'title' => $source['name']))
                 . html::div(null, html::span('name', rcube::Q($source['name']))
                     . html::br()
                     . html::span('description', rcube::Q($source['description']))
                     . $form->show()
                 );
 
             $table->add(array('id' => $id, 'colspan' => 2, 'class' => 'source'), $row);
         }
 
         $out = $table->show() . $this->folder_auth_options(array('suffix' => '-form'));
 
         // add form tag around text field
         if (empty($attrib['form'])) {
             $out = $this->rc->output->form_tag($attrib, $out);
         }
 
         $this->plugin->add_label('foldermounting', 'foldermountnotice', 'foldermount',
             'save', 'cancel', 'folderauthtitle', 'authenticating'
         );
         $this->rc->output->add_gui_object('folder-mount-form', $attrib['id']);
 
         return $out;
     }
 
     /**
      * Template object for folder authentication options
      */
     public function folder_auth_options($attrib)
     {
         $checkbox = new html_checkbox(array(
             'name'  => 'store_passwords',
             'value' => '1',
             'id'    => 'auth-pass-checkbox' . $attrib['suffix'],
         ));
 
         return html::div('auth-options', $checkbox->show(). '&nbsp;'
             . html::label('auth-pass-checkbox' . $attrib['suffix'], $this->plugin->gettext('storepasswords'))
             . html::span('description', $this->plugin->gettext('storepasswordsdesc'))
         );
     }
 
     /**
      * Template object for file_edit form
      */
     public function file_edit_form($attrib)
     {
         $attrib['name'] = 'file-edit-form';
         if (empty($attrib['id'])) {
             $attrib['id'] = 'file-edit-form';
         }
 
         $input_name = new html_inputfield(array('id' => 'file-name', 'name' => 'name', 'size' => 30));
         $table      = new html_table(array('cols' => 2, 'class' => 'propform'));
 
         $table->add('title', html::label('file-name', rcube::Q($this->plugin->gettext('filename'))));
         $table->add(null, $input_name->show());
 
         $out = $table->show();
 
         // add form tag around text field
         if (empty($attrib['form'])) {
             $out = $this->rc->output->form_tag($attrib, $out);
         }
 
         $this->plugin->add_label('save', 'cancel', 'fileupdating', 'fileedit');
         $this->rc->output->add_gui_object('file-edit-form', $attrib['id']);
 
         return $out;
     }
 
     /**
      * Template object for file search form in "From cloud" dialog
      */
     public function file_search_form($attrib)
     {
         $attrib['name'] = '_q';
 
         if (empty($attrib['id'])) {
             $attrib['id'] = 'filesearchbox';
         }
         if ($attrib['type'] == 'search' && !$this->rc->output->browser->khtml) {
             unset($attrib['type'], $attrib['results']);
         }
 
         $input_q = new html_inputfield($attrib);
         $out = $input_q->show();
 
         // add some labels to client
         $this->rc->output->add_label('searching');
         $this->rc->output->add_gui_object('filesearchbox', $attrib['id']);
 
         // add form tag around text field
         if (empty($attrib['form'])) {
             $out = $this->rc->output->form_tag(array(
                     'action'   => '?_task=files',
                     'name'     => "filesearchform",
                     'onsubmit' => rcmail_output::JS_OBJECT_NAME . ".command('files-search'); return false",
                 ), $out);
         }
 
         return $out;
     }
 
     /**
      * Template object for files list
      */
     public function file_list($attrib)
     {
         // define list of cols to be displayed based on parameter or config
         if (empty($attrib['columns'])) {
             $list_cols     = $this->rc->config->get('kolab_files_list_cols');
             $dont_override = $this->rc->config->get('dont_override');
             $a_show_cols = is_array($list_cols) ? $list_cols : array('name');
             $this->rc->output->set_env('col_movable', !in_array('kolab_files_list_cols', (array)$dont_override));
         }
         else {
             $columns     = str_replace(array("'", '"'), '', $attrib['columns']);
             $a_show_cols = preg_split('/[\s,;]+/', $columns);
         }
 
         // make sure 'name' and 'options' column is present
         if (!in_array('name', $a_show_cols)) {
             array_unshift($a_show_cols, 'name');
         }
         if (!in_array('options', $a_show_cols)) {
             array_unshift($a_show_cols, 'options');
         }
 
         $attrib['columns'] = $a_show_cols;
 
         // save some variables for use in ajax list
         $_SESSION['kolab_files_list_attrib'] = $attrib;
 
         // For list in dialog(s) remove all option-like columns
         if ($this->rc->task != 'files') {
             $a_show_cols = array_intersect($a_show_cols, $this->sort_cols);
         }
 
         // set default sort col/order to session
         if (!isset($_SESSION['kolab_files_sort_col']))
             $_SESSION['kolab_files_sort_col'] = $this->rc->config->get('kolab_files_sort_col') ?: 'name';
         if (!isset($_SESSION['kolab_files_sort_order']))
             $_SESSION['kolab_files_sort_order'] = strtoupper($this->rc->config->get('kolab_files_sort_order') ?: 'asc');
 
         // set client env
         $this->rc->output->add_gui_object('filelist', $attrib['id']);
         $this->rc->output->set_env('sort_col', $_SESSION['kolab_files_sort_col']);
         $this->rc->output->set_env('sort_order', $_SESSION['kolab_files_sort_order']);
         $this->rc->output->set_env('coltypes', $a_show_cols);
         $this->rc->output->set_env('search_threads', $this->rc->config->get('kolab_files_search_threads'));
 
         $this->rc->output->include_script('list.js');
 
         // attach css rules for mimetype icons
         $this->plugin->include_stylesheet($this->url . '/skins/default/images/mimetypes/style.css');
 
         $thead = '';
         foreach ($this->file_list_head($attrib, $a_show_cols) as $cell) {
             $thead .= html::tag('th', array('class' => $cell['className'], 'id' => $cell['id']), $cell['html']);
         }
 
         return html::tag('table', $attrib,
             html::tag('thead', null, html::tag('tr', null, $thead)) . html::tag('tbody', null, ''),
             array('style', 'class', 'id', 'cellpadding', 'cellspacing', 'border', 'summary'));
     }
 
     /**
      * Creates <THEAD> for message list table
      */
     protected function file_list_head($attrib, $a_show_cols)
     {
         $skin_path = $_SESSION['skin_path'];
 //        $image_tag = html::img(array('src' => "%s%s", 'alt' => "%s"));
 
         // check to see if we have some settings for sorting
         $sort_col   = $_SESSION['kolab_files_sort_col'];
         $sort_order = $_SESSION['kolab_files_sort_order'];
 
         $dont_override  = (array)$this->rc->config->get('dont_override');
         $disabled_sort  = in_array('message_sort_col', $dont_override);
         $disabled_order = in_array('message_sort_order', $dont_override);
 
         $this->rc->output->set_env('disabled_sort_col', $disabled_sort);
         $this->rc->output->set_env('disabled_sort_order', $disabled_order);
 
         // define sortable columns
         if ($disabled_sort)
             $a_sort_cols = $sort_col && !$disabled_order ? array($sort_col) : array();
         else
             $a_sort_cols = $this->sort_cols;
 
         if (!empty($attrib['optionsmenuicon'])) {
             $onclick = 'return ' . rcmail_output::JS_OBJECT_NAME . ".command('menu-open', 'filelistmenu', this, event)";
             $inner   = $this->rc->gettext('listoptions');
 
             if (is_string($attrib['optionsmenuicon']) && $attrib['optionsmenuicon'] != 'true') {
                 $inner = html::img(array('src' => $skin_path . $attrib['optionsmenuicon'], 'alt' => $this->rc->gettext('listoptions')));
             }
 
             $list_menu = html::a(array(
                 'href'     => '#list-options',
                 'onclick'  => $onclick,
                 'class'    => 'listmenu',
                 'id'       => 'listmenulink',
                 'title'    => $this->rc->gettext('listoptions'),
                 'tabindex' => '0',
             ), $inner);
         }
         else {
             $list_menu = '';
         }
 
         $cells = array();
 
         foreach ($a_show_cols as $col) {
             // get column name
             switch ($col) {
 /*
             case 'status':
                 $col_name = '<span class="' . $col .'">&nbsp;</span>';
                 break;
 */
             case 'options':
                 $col_name = $list_menu;
                 break;
             default:
                 $col_name = rcube::Q($this->plugin->gettext($col));
             }
 
             // make sort links
             if (in_array($col, $a_sort_cols)) {
                 $col_name = html::a(array(
                         'href'    => "#sort",
                         'onclick' => 'return ' . rcmail_output::JS_OBJECT_NAME . ".command('files-sort','$col',this)",
                         'title'   => $this->plugin->gettext('sortby')
                     ), $col_name);
             }
             else if ($col_name[0] != '<')
                 $col_name = '<span class="' . $col .'">' . $col_name . '</span>';
 
             $sort_class = $col == $sort_col && !$disabled_order ? " sorted$sort_order" : '';
             $class_name = $col.$sort_class;
 
             // put it all together
             $cells[] = array('className' => $class_name, 'id' => "rcm$col", 'html' => $col_name);
         }
 
         return $cells;
     }
 
     /**
      * Update files list object
      */
     protected function file_list_update($prefs)
     {
         $attrib = $_SESSION['kolab_files_list_attrib'];
 
         if (!empty($prefs['kolab_files_list_cols'])) {
             $attrib['columns'] = $prefs['kolab_files_list_cols'];
             $_SESSION['kolab_files_list_attrib'] = $attrib;
         }
 
         $a_show_cols = $attrib['columns'];
         $head        = '';
 
         foreach ($this->file_list_head($attrib, $a_show_cols) as $cell) {
             $head .= html::tag('td', array('class' => $cell['className'], 'id' => $cell['id']), $cell['html']);
         }
 
         $head = html::tag('tr', null, $head);
 
         $this->rc->output->set_env('coltypes', $a_show_cols);
         $this->rc->output->command('files_list_update', $head);
     }
 
     /**
      * Template object for file info box
      */
     public function file_info_box($attrib)
     {
         // print_r($this->file_data, true);
         $table = new html_table(array('cols' => 2, 'class' => $attrib['class']));
 
         // file name
         $table->add('label', $this->plugin->gettext('name').':');
         $table->add('data filename', $this->file_data['name']);
 
         // file type
         // @TODO: human-readable type name
         $table->add('label', $this->plugin->gettext('type').':');
         $table->add('data filetype', $this->file_data['type']);
 
         // file size
         $table->add('label', $this->plugin->gettext('size').':');
         $table->add('data filesize', $this->rc->show_bytes($this->file_data['size']));
 
         // file modification time
         $table->add('label', $this->plugin->gettext('mtime').':');
         $table->add('data filemtime', $this->file_data['mtime']);
 
         // @TODO: for images: width, height, color depth, etc.
         // @TODO: for text files: count of characters, lines, words
 
         return $table->show();
     }
 
     /**
      * Template object for file preview frame
      */
     public function file_preview_frame($attrib)
     {
         if (empty($attrib['id'])) {
             $attrib['id'] = 'filepreviewframe';
         }
 
         if ($frame = $this->file_data['viewer']['frame']) {
             return $frame;
         }
 
         if ($href = $this->file_data['viewer']['href']) {
             // file href attribute must be an absolute URL (Bug #2063)
             if (!empty($href)) {
                 if (!preg_match('|^https?://|', $href)) {
                     $href = $this->url . '/api/' . $href;
                 }
             }
         }
         else {
             $token = $this->get_api_token();
             $href  = $this->url . '/api/?method=file_get'
                 . '&file=' . urlencode($this->file_data['filename'])
                 . '&token=' . urlencode($token);
         }
 
         $this->rc->output->add_gui_object('preview_frame', $attrib['id']);
 
         $attrib['allowfullscreen'] = true;
         $attrib['src']             = $href;
         $attrib['onload']          = 'kolab_files_frame_load(this)';
 
         return html::iframe($attrib);
     }
 
     /**
      * Template object for quota display
      */
     public function quota_display($attrib)
     {
         if (!$attrib['id']) {
             $attrib['id'] = 'rcmquotadisplay';
         }
 
         $quota_type = !empty($attrib['display']) ? $attrib['display'] : 'text';
 
         $this->rc->output->add_gui_object('quotadisplay', $attrib['id']);
         $this->rc->output->set_env('quota_type', $quota_type);
 
         // get quota
         $token   = $this->get_api_token();
         $request = $this->get_request(array('method' => 'quota'), $token);
 
         // send request to the API
         try {
             $response = $request->send();
             $status   = $response->getStatus();
             $body     = @json_decode($response->getBody(), true);
 
             if ($status == 200 && $body['status'] == 'OK') {
                 $quota = $body['result'];
             }
             else {
                 throw new Exception($body['reason']);
             }
         }
         catch (Exception $e) {
             rcube::raise_error($e, true, false);
             $quota = array('total' => 0, 'percent' => 0);
         }
 
         $quota = rcube_output::json_serialize($quota);
 
         $this->rc->output->add_script(rcmail_output::JS_OBJECT_NAME . ".files_set_quota($quota);", 'docready');
 
         return html::span($attrib, '');
     }
 
     /**
      * Get API token for current user session, authenticate if needed
      */
     public function get_api_token()
     {
         $token = $_SESSION['kolab_files_token'];
         $time  = $_SESSION['kolab_files_time'];
 
         if ($token && time() - $this->timeout < $time) {
             if (time() - $time <= $this->timeout / 2) {
                 return $token;
             }
         }
 
         $request = $this->get_request(array('method' => 'ping'), $token);
 
         try {
             $url = $request->getUrl();
 
             // Send ping request
             if ($token) {
                 $url->setQueryVariables(array('method' => 'ping'));
                 $request->setUrl($url);
                 $response = $request->send();
                 $status   = $response->getStatus();
 
                 if ($status == 200 && ($body = json_decode($response->getBody(), true))) {
                     if ($body['status'] == 'OK') {
                         $_SESSION['kolab_files_time']  = time();
                         return $token;
                     }
                 }
             }
 
             // Go with authenticate request
             $url->setQueryVariables(array('method' => 'authenticate', 'version' => self::API_VERSION));
             $request->setUrl($url);
             $request->setAuth($this->rc->user->get_username(), $this->rc->decrypt($_SESSION['password']));
             $response = $request->send();
             $status   = $response->getStatus();
 
             if ($status == 200 && ($body = json_decode($response->getBody(), true))) {
                 $token = $body['result']['token'];
 
                 if ($token) {
                     $_SESSION['kolab_files_token'] = $token;
                     $_SESSION['kolab_files_time']  = time();
                     $_SESSION['kolab_files_caps']  = $body['result']['capabilities'];
                 }
             }
             else {
                 throw new Exception(sprintf("Authenticate error (Status: %d)", $status));
             }
         }
         catch (Exception $e) {
             rcube::raise_error($e, true, false);
         }
 
         return $token;
     }
 
     /**
      * Initialize HTTP_Request object
      */
     protected function get_request($get = null, $token = null)
     {
         $url = $this->url . '/api/';
 
         if (!$this->request) {
             $config = array(
                 'store_body'       => true,
                 'follow_redirects' => true,
             );
 
             $this->request = libkolab::http_request($url, 'GET', $config);
         }
         else {
             // cleanup
             try {
                 $this->request->setBody('');
                 $this->request->setUrl($url);
                 $this->request->setMethod(HTTP_Request2::METHOD_GET);
             }
             catch (Exception $e) {
                 rcube::raise_error($e, true, true);
             }
         }
 
         if ($token) {
             $this->request->setHeader('X-Session-Token', $token);
         }
 
         if (!empty($get)) {
             $url = $this->request->getUrl();
             $url->setQueryVariables($get);
             $this->request->setUrl($url);
         }
 
         // some HTTP server configurations require this header
         $this->request->setHeader('accept', "application/json,text/javascript,*/*");
 
         return $this->request;
     }
 
     /**
      * Handler for main files interface (Files task)
      */
     protected function action_index()
     {
         $this->plugin->add_label(
-            'folderdeleting', 'folderdeleteconfirm', 'folderdeletenotice',
-            'uploading', 'attaching', 'uploadsizeerror',
+            'uploading', 'attaching', 'searching', 'uploadsizeerror',
             'filedeleting', 'filedeletenotice', 'filedeleteconfirm',
             'filemoving', 'filemovenotice', 'filemoveconfirm', 'filecopying', 'filecopynotice',
-            'collection_audio', 'collection_video', 'collection_image', 'collection_document',
             'fileskip', 'fileskipall', 'fileoverwrite', 'fileoverwriteall'
         );
 
+        $this->folder_list_env();
+
         $this->rc->output->add_label('uploadprogress', 'GB', 'MB', 'KB', 'B');
         $this->rc->output->set_pagetitle($this->plugin->gettext('files'));
         $this->rc->output->set_env('file_mimetypes', $this->get_mimetypes());
         $this->rc->output->set_env('files_quota', $_SESSION['kolab_files_caps']['QUOTA']);
         $this->rc->output->set_env('files_max_upload', $_SESSION['kolab_files_caps']['MAX_UPLOAD']);
         $this->rc->output->set_env('files_progress_name', $_SESSION['kolab_files_caps']['PROGRESS_NAME']);
         $this->rc->output->set_env('files_progress_time', $_SESSION['kolab_files_caps']['PROGRESS_TIME']);
         $this->rc->output->send('kolab_files.files');
     }
 
     /**
      * Handler for preferences save action
      */
     protected function action_prefs()
     {
         $dont_override = (array)$this->rc->config->get('dont_override');
         $prefs = array();
         $opts  = array(
             'kolab_files_sort_col' => true,
             'kolab_files_sort_order' => true,
             'kolab_files_list_cols' => false,
         );
 
         foreach ($opts as $o => $sess) {
             if (isset($_POST[$o]) && !in_array($o, $dont_override)) {
                 $prefs[$o] = rcube_utils::get_input_value($o, rcube_utils::INPUT_POST);
                 if ($sess) {
                     $_SESSION[$o] = $prefs[$o];
                 }
 
                 if ($o == 'kolab_files_list_cols') {
                     $update_list = true;
                 }
             }
         }
 
         // save preference values
         if (!empty($prefs)) {
             $this->rc->user->save_prefs($prefs);
         }
 
         if (!empty($update_list)) {
             $this->file_list_update($prefs);
         }
 
         $this->rc->output->send();
     }
 
     /**
      * Handler for file open action
      */
     protected function action_open()
     {
         $file = rcube_utils::get_input_value('file', rcube_utils::INPUT_GET);
 
         // get file info
         $token   = $this->get_api_token();
         $request = $this->get_request(array(
             'method' => 'file_info',
             'file'   => $file,
             'viewer' => !empty($_GET['viewer']),
             ), $token);
 
         // send request to the API
         try {
             $response = $request->send();
             $status   = $response->getStatus();
             $body     = @json_decode($response->getBody(), true);
 
             if ($status == 200 && $body['status'] == 'OK') {
                 $this->file_data = $body['result'];
             }
             else {
                 throw new Exception($body['reason']);
             }
         }
         catch (Exception $e) {
             rcube::raise_error(array(
                 'code' => 500, 'type' => 'php', 'line' => __LINE__, 'file' => __FILE__,
                 'message' => $e->getMessage()),
                 true, true);
         }
 
         $this->file_data['filename'] = $file;
 
         $this->plugin->add_label('filedeleteconfirm', 'filedeleting', 'filedeletenotice');
 
         // register template objects for dialogs (and main interface)
         $this->rc->output->add_handlers(array(
             'fileinfobox'      => array($this, 'file_info_box'),
             'filepreviewframe' => array($this, 'file_preview_frame'),
         ));
 
         // this one is for styling purpose
         $this->rc->output->set_env('extwin', true);
         $this->rc->output->set_env('file', $file);
         $this->rc->output->set_env('file_data', $this->file_data);
         $this->rc->output->set_pagetitle(rcube::Q($file));
         $this->rc->output->send('kolab_files.filepreview');
     }
 
     /**
      * Handler for "save all attachments into cloud" action
      */
     protected function action_save_file()
     {
 //        $source = rcube_utils::get_input_value('source', rcube_utils::INPUT_POST);
         $uid    = rcube_utils::get_input_value('uid', rcube_utils::INPUT_POST);
         $dest   = rcube_utils::get_input_value('dest', rcube_utils::INPUT_POST);
         $id     = rcube_utils::get_input_value('id', rcube_utils::INPUT_POST);
         $name   = rcube_utils::get_input_value('name', rcube_utils::INPUT_POST);
 
         $temp_dir = unslashify($this->rc->config->get('temp_dir'));
         $message  = new rcube_message($uid);
         $request  = $this->get_request();
         $url      = $request->getUrl();
         $files    = array();
         $errors   = array();
         $attachments = array();
 
         $request->setMethod(HTTP_Request2::METHOD_POST);
         $request->setHeader('X-Session-Token', $this->get_api_token());
         $url->setQueryVariables(array('method' => 'file_upload', 'folder' => $dest));
         $request->setUrl($url);
 
         foreach ($message->attachments as $attach_prop) {
             if (empty($id) || $id == $attach_prop->mime_id) {
                 $filename = strlen($name) ? $name : rcmail_attachment_name($attach_prop, true);
                 $attachments[$filename] = $attach_prop;
             }
         }
 
         // @TODO: handle error
         // @TODO: implement file upload using file URI instead of body upload
 
         foreach ($attachments as $attach_name => $attach_prop) {
             $path = tempnam($temp_dir, 'rcmAttmnt');
 
             // save attachment to file
             if ($fp = fopen($path, 'w+')) {
                 $message->get_part_body($attach_prop->mime_id, false, 0, $fp);
             }
             else {
                 $errors[] = true;
                 rcube::raise_error(array(
                     'code' => 500, 'type' => 'php', 'line' => __LINE__, 'file' => __FILE__,
                     'message' => "Unable to save attachment into file $path"),
                     true, false);
                 continue;
             }
 
             fclose($fp);
 
             // send request to the API
             try {
                 $request->setBody('');
                 $request->addUpload('file[]', $path, $attach_name, $attach_prop->mimetype);
                 $response = $request->send();
                 $status   = $response->getStatus();
                 $body     = @json_decode($response->getBody(), true);
 
                 if ($status == 200 && $body['status'] == 'OK') {
                     $files[] = $attach_name;
                 }
                 else {
                     throw new Exception($body['reason']);
                 }
             }
             catch (Exception $e) {
                 unlink($path);
                 $errors[] = $e->getMessage();
                 rcube::raise_error(array(
                     'code' => 500, 'type' => 'php', 'line' => __LINE__, 'file' => __FILE__,
                     'message' => $e->getMessage()),
                     true, false);
                 continue;
             }
 
             // clean up
             unlink($path);
             $request->setBody('');
         }
 
         if ($count = count($files)) {
             $msg = $this->plugin->gettext(array('name' => 'saveallnotice', 'vars' => array('n' => $count)));
             $this->rc->output->show_message($msg, 'confirmation');
         }
         if ($count = count($errors)) {
             $msg = $this->plugin->gettext(array('name' => 'saveallerror', 'vars' => array('n' => $count)));
             $this->rc->output->show_message($msg, 'error');
         }
 
         // @TODO: update quota indicator, make this optional in case files aren't stored in IMAP
 
         $this->rc->output->send();
     }
 
     /**
      * Handler for "add attachments from the cloud" action
      */
     protected function action_attach_file()
     {
         $files      = rcube_utils::get_input_value('files', rcube_utils::INPUT_POST);
         $uploadid   = rcube_utils::get_input_value('uploadid', rcube_utils::INPUT_POST);
         $COMPOSE_ID = rcube_utils::get_input_value('id', rcube_utils::INPUT_POST);
         $COMPOSE    = null;
         $errors     = array();
 
         if ($COMPOSE_ID && $_SESSION['compose_data_'.$COMPOSE_ID]) {
             $COMPOSE =& $_SESSION['compose_data_'.$COMPOSE_ID];
         }
 
         if (!$COMPOSE) {
             die("Invalid session var!");
         }
 
         // attachment upload action
         if (!is_array($COMPOSE['attachments'])) {
             $COMPOSE['attachments'] = array();
         }
 
         // clear all stored output properties (like scripts and env vars)
         $this->rc->output->reset();
 
         $temp_dir = unslashify($this->rc->config->get('temp_dir'));
         $request  = $this->get_request();
         $url      = $request->getUrl();
 
         // Use observer object to store HTTP response into a file
         require_once $this->plugin->home . DIRECTORY_SEPARATOR . 'lib' . DIRECTORY_SEPARATOR . 'kolab_files_observer.php';
         $observer = new kolab_files_observer();
 
         $request->setHeader('X-Session-Token', $this->get_api_token());
 
         // download files from the API and attach them
         foreach ($files as $file) {
             // decode filename
             $file = urldecode($file);
 
             // get file information
             try {
                 $url->setQueryVariables(array('method' => 'file_info', 'file' => $file));
                 $request->setUrl($url);
                 $response = $request->send();
                 $status   = $response->getStatus();
                 $body     = @json_decode($response->getBody(), true);
 
                 if ($status == 200 && $body['status'] == 'OK') {
                     $file_params = $body['result'];
                 }
                 else {
                     throw new Exception($body['reason']);
                 }
             }
             catch (Exception $e) {
                 $errors[] = $e->getMessage();
                 rcube::raise_error(array(
                     'code' => 500, 'type' => 'php', 'line' => __LINE__, 'file' => __FILE__,
                     'message' => $e->getMessage()),
                     true, false);
                 continue;
             }
 
             // set location of downloaded file
             $path = tempnam($temp_dir, 'rcmAttmnt');
             $observer->set_file($path);
 
             // download file
             try {
                 $url->setQueryVariables(array('method' => 'file_get', 'file' => $file));
                 $request->setUrl($url);
                 $request->attach($observer);
                 $response = $request->send();
                 $status   = $response->getStatus();
                 $response->getBody(); // returns nothing
                 $request->detach($observer);
 
                 if ($status != 200 || !file_exists($path)) {
                     throw new Exception("Unable to save file");
                 }
             }
             catch (Exception $e) {
                 $errors[] = $e->getMessage();
                 rcube::raise_error(array(
                     'code' => 500, 'type' => 'php', 'line' => __LINE__, 'file' => __FILE__,
                     'message' => $e->getMessage()),
                     true, false);
                 continue;
             }
 
             $attachment = array(
                 'path' => $path,
                 'size' => $file_params['size'],
                 'name' => $file_params['name'],
                 'mimetype' => $file_params['type'],
                 'group' => $COMPOSE_ID,
             );
 
             $attachment = $this->rc->plugins->exec_hook('attachment_save', $attachment);
 
             if ($attachment['status'] && !$attachment['abort']) {
                 $id = $attachment['id'];
 
                 // store new attachment in session
                 unset($attachment['data'], $attachment['status'], $attachment['abort']);
                 $COMPOSE['attachments'][$id] = $attachment;
 
                 if (($icon = $COMPOSE['deleteicon']) && is_file($icon)) {
                     $button = html::img(array(
                         'src' => $icon,
                         'alt' => $this->rc->gettext('delete')
                     ));
                 }
                 else {
                     $button = rcube::Q($this->rc->gettext('delete'));
                 }
 
                 $content = html::a(array(
                     'href' => "#delete",
                     'onclick' => sprintf("return %s.command('remove-attachment','rcmfile%s', this)", rcmail_output::JS_OBJECT_NAME, $id),
                     'title' => $this->rc->gettext('delete'),
                     'class' => 'delete',
                 ), $button);
 
                 $content .= rcube::Q($attachment['name']);
 
                 $this->rc->output->command('add2attachment_list', "rcmfile$id", array(
                     'html'      => $content,
                     'name'      => $attachment['name'],
                     'mimetype'  => $attachment['mimetype'],
                     'classname' => rcmail_filetype2classname($attachment['mimetype'], $attachment['name']),
                     'complete'  => true), $uploadid);
             }
             else if ($attachment['error']) {
                 $errors[] = $attachment['error'];
             }
             else {
                 $errors[] = $this->plugin->gettext('attacherror');
             }
         }
 
         if (!empty($errors)) {
             $this->rc->output->command('display_message', $this->plugin->gettext('attacherror'), 'error');
             $this->rc->output->command('remove_from_attachment_list', $uploadid);
         }
 
         // send html page with JS calls as response
         $this->rc->output->command('auto_save_start', false);
         $this->rc->output->send();
     }
 
     /**
      * Returns mimetypes supported by File API viewers
      */
     protected function get_mimetypes()
     {
         $token   = $this->get_api_token();
         $request = $this->get_request(array('method' => 'mimetypes'), $token);
 
         // send request to the API
         try {
             $response = $request->send();
             $status   = $response->getStatus();
             $body     = @json_decode($response->getBody(), true);
 
             if ($status == 200 && $body['status'] == 'OK') {
                 $mimetypes = $body['result'];
             }
             else {
                 throw new Exception($body['reason']);
             }
         }
         catch (Exception $e) {
             rcube::raise_error(array(
                 'code' => 500, 'type' => 'php', 'line' => __LINE__, 'file' => __FILE__,
                 'message' => $e->getMessage()),
                 true, false);
         }
 
         return $mimetypes;
     }
 
     /**
      * Get list of available external storage drivers
      */
     protected function get_external_storage_drivers()
     {
         // first get configured sources from Chwala
         $token   = $this->get_api_token();
         $request = $this->get_request(array('method' => 'folder_types'), $token);
 
         // send request to the API
         try {
             $response = $request->send();
             $status   = $response->getStatus();
             $body     = @json_decode($response->getBody(), true);
 
             if ($status == 200 && $body['status'] == 'OK') {
                 $sources = $body['result'];
             }
             else {
                 throw new Exception($body['reason']);
             }
         }
         catch (Exception $e) {
             rcube::raise_error($e, true, false);
             return;
         }
 
         $this->rc->output->set_env('external_sources', $sources);
     }
+
+    /**
+     * Registers translation labels for folder lists in UI
+     */
+    protected function folder_list_env()
+    {
+        // folder list and actions
+        $this->plugin->add_label(
+            'folderdeleting', 'folderdeleteconfirm', 'folderdeletenotice',
+            'collection_audio', 'collection_video', 'collection_image', 'collection_document',
+            'additionalfolders', 'listpermanent'
+        );
+        $this->rc->output->add_label('foldersubscribing', 'foldersubscribed',
+            'folderunsubscribing', 'folderunsubscribed', 'searching'
+        );
+
+        $this->rc->output->set_env('files_caps', $_SESSION['kolab_files_caps']);
+    }
 }
diff --git a/plugins/kolab_files/localization/en_US.inc b/plugins/kolab_files/localization/en_US.inc
index 50675288..d3f1a308 100644
--- a/plugins/kolab_files/localization/en_US.inc
+++ b/plugins/kolab_files/localization/en_US.inc
@@ -1,106 +1,108 @@
 <?php
 
 /**
  * Localizations for the Kolab Files plugin
  *
  * Copyright (C) 2014, Kolab Systems AG
  *
  * For translation see https://www.transifex.com/projects/p/kolab/resource/kolab_files/
  */
 
 $labels['files'] = 'Files';
 $labels['filepreview'] = 'File preview';
 $labels['saveall'] = 'Save all to cloud...';
 $labels['saveto'] = 'Save to cloud...';
 $labels['saveas'] = 'Save as:';
 $labels['create'] = 'Create';
 $labels['save'] = 'Save';
 $labels['cancel'] = 'Cancel';
 $labels['fromcloud'] = 'From cloud...';
 $labels['selectfiles'] = 'Select file(s) to attach...';
 $labels['attachsel'] = 'Attach selected';
 $labels['foldercreate'] = 'Create folder';
 $labels['folderedit'] = 'Edit folder';
 $labels['foldermount'] = 'Add storage';
 $labels['folderdelete'] = 'Delete folder';
 
 $labels['folderinside'] = 'Insert inside';
 $labels['foldername'] = 'Folder name';
 $labels['name'] = 'Name';
 $labels['mtime'] = 'Modified';
 $labels['type'] = 'Type';
 
 $labels['upload'] = 'Upload';
 $labels['uploadfile'] = 'Upload file(s)';
 $labels['get'] = 'Download';
 $labels['getfile'] = 'Download file';
 $labels['view'] = 'View';
 $labels['viewfile'] = 'View file';
 $labels['rename'] = 'Rename file';
 $labels['deletefile'] = 'Delete file(s)';
 $labels['edit'] = 'Edit';
 $labels['editfile'] = 'Edit file';
 $labels['save'] = 'Save';
 $labels['savefile'] = 'Save file';
 $labels['printfile'] = 'Print file';
 $labels['fileedit'] = 'File properties';
 
 $labels['collection_audio'] = 'Audio';
 $labels['collection_video'] = 'Video';
 $labels['collection_image'] = 'Images';
 $labels['collection_document'] = 'Documents';
 
 $labels['uploading'] = 'Uploading file(s)...';
 $labels['attaching'] = 'Attaching file(s)...';
 $labels['authenticating'] = 'Authenticating...';
 $labels['foldercreating'] = 'Creating folder...';
 $labels['folderupdating'] = 'Updating folder...';
 $labels['foldermounting'] = 'Adding external storage...';
 $labels['folderdeleting'] = 'Deleting folder...';
 $labels['folderdeleteconfirm'] = 'Are you sure you want to delete selected folder?';
 $labels['folderdeletenotice'] = 'Folder deleted successfully.';
 $labels['folderupdatenotice'] = 'Folder updated successfully.';
 $labels['foldercreatenotice'] = 'Folder created successfully.';
 $labels['foldermountnotice'] = 'Storage added successfully.';
 $labels['folderauthtitle'] = 'Logon to $title';
 $labels['saveallnotice'] = 'Successfully saved $n file(s).';
 $labels['saveallerror'] = 'Saving $n file(s) failed.';
 $labels['attacherror'] = 'Failed to attach file(s) from the cloud';
 $labels['fileupdating'] = 'Updating file...';
 $labels['filemoving'] = 'Moving file(s)...';
 $labels['filecopying'] = 'Copying file(s)...';
 $labels['filedeleting'] = 'Deleting file(s)...';
 $labels['filedeleteconfirm'] = 'Are you sure you want to delete selected files?';
 $labels['filedeletenotice'] = 'File(s) deleted successfully.';
 $labels['filemovenotice'] = 'File(s) moved successfully.';
 $labels['filecopynotice'] = 'File(s) copied successfully.';
 $labels['uploadsizeerror'] = 'Maximum file size ($size) exceeded!';
 
+$labels['listpermanent'] = 'List permanently';
+$labels['additionalfolders'] = 'Additional folders';
 $labels['allfolders'] = 'search in all folders';
 $labels['fileskip'] = 'Skip';
 $labels['fileskipall'] = 'Skip all';
 $labels['fileoverwrite'] = 'Overwrite';
 $labels['fileoverwriteall'] = 'Overwrite all';
 $labels['filemoveconfirm'] = 'This action is going to overwrite the destination file: <b>$file</b>.';
 
 $labels['storepasswords'] = 'remember password';
 $labels['storepasswordsdesc'] = 'Stored passwords will be encrypted. Enable this if you do not want to be asked for the password on every login or you want this storage to be available via WebDAV.';
 
 $labels['arialabelsearchform'] = 'Files search form';
 $labels['arialabelquicksearchbox'] = 'Search input';
 $labels['arialabellistoptions'] = 'Files list options';
 $labels['arialabelfolderoptions'] = 'Folder actions';
 $labels['arialabelfileeditform'] = 'File editing form';
 $labels['arialabelfilelist'] = 'List of files';
 $labels['arialabelfoldercreateform'] = 'Folder creation form';
 $labels['arialabelfoldereditform'] = 'Folder editing form';
 $labels['arialabelfoldermountform'] = 'External storage form';
 $labels['arialabelfolderauthform'] = 'External storage authentication form';
 $labels['arialabelfolderlist'] = 'Folder/Collection selection';
 $labels['arialabelfileselectdialog'] = 'File selection dialog';
 $labels['arialabelattachmentoptions'] = 'Attachment save options';
 $labels['arialabelfilesavedialog'] = 'File(s) saving dialog';
 $labels['arialabelfileprops'] = 'File properties';
 $labels['arialabelfilecontent'] = 'File content';
 
 ?>
diff --git a/plugins/kolab_files/skins/larry/images/listicons.png b/plugins/kolab_files/skins/larry/images/listicons.png
new file mode 100644
index 00000000..5b5ca85b
Binary files /dev/null and b/plugins/kolab_files/skins/larry/images/listicons.png differ